{ "schema": "cie-topical-past-papers/v1", "subject": "9618", "subject_name": "Computer Science", "syllabus_url": "https://www.cambridgeinternational.org/Images/697372-2026-syllabus.pdf", "generated": "2026-08-14", "coverage": { "years": [ 2021, 2022, 2023, 2024, 2025, 2026 ], "sessions": [ "May/June", "Oct/Nov" ], "papers": [ "31", "32", "33", "41", "42", "43" ], "available_papers": 58, "missing_papers": [ { "year": 2021, "session": "Oct/Nov", "variant": "33", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_33.pdf?download=true", "reason": "not available from the local downloader/source search" }, { "year": 2021, "session": "Oct/Nov", "variant": "43", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_43.pdf?download=true", "reason": "not available from the local downloader/source search" }, { "year": 2026, "session": "May/June", "variant": "31", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-May-June/9618_s26_qp_31.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "May/June", "variant": "32", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-May-June/9618_s26_qp_32.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "May/June", "variant": "33", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-May-June/9618_s26_qp_33.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "May/June", "variant": "41", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-May-June/9618_s26_qp_41.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "May/June", "variant": "42", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-May-June/9618_s26_qp_42.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "May/June", "variant": "43", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-May-June/9618_s26_qp_43.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "Oct/Nov", "variant": "31", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-Oct-Nov/9618_w26_qp_31.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "Oct/Nov", "variant": "32", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-Oct-Nov/9618_w26_qp_32.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "Oct/Nov", "variant": "33", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-Oct-Nov/9618_w26_qp_33.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "Oct/Nov", "variant": "41", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-Oct-Nov/9618_w26_qp_41.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "Oct/Nov", "variant": "42", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-Oct-Nov/9618_w26_qp_42.pdf?download=true", "reason": "unpublished as of 2026-08-14" }, { "year": 2026, "session": "Oct/Nov", "variant": "43", "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2026-Oct-Nov/9618_w26_qp_43.pdf?download=true", "reason": "unpublished as of 2026-08-14" } ] }, "topics": [ { "number": 13, "label": "Data representation", "slug": "9618-topic-13-data-representation", "questions_html": "9618-topic-13-data-representation/questions.html", "answers_html": "9618-topic-13-data-representation/answers.html" }, { "number": 14, "label": "Communication and internet technologies", "slug": "9618-topic-14-communication-and-internet-technologies", "questions_html": "9618-topic-14-communication-and-internet-technologies/questions.html", "answers_html": "9618-topic-14-communication-and-internet-technologies/answers.html" }, { "number": 15, "label": "Hardware and virtual machines", "slug": "9618-topic-15-hardware-and-virtual-machines", "questions_html": "9618-topic-15-hardware-and-virtual-machines/questions.html", "answers_html": "9618-topic-15-hardware-and-virtual-machines/answers.html" }, { "number": 16, "label": "System software", "slug": "9618-topic-16-system-software", "questions_html": "9618-topic-16-system-software/questions.html", "answers_html": "9618-topic-16-system-software/answers.html" }, { "number": 17, "label": "Security", "slug": "9618-topic-17-security", "questions_html": "9618-topic-17-security/questions.html", "answers_html": "9618-topic-17-security/answers.html" }, { "number": 18, "label": "Artificial intelligence (AI)", "slug": "9618-topic-18-artificial-intelligence", "questions_html": "9618-topic-18-artificial-intelligence/questions.html", "answers_html": "9618-topic-18-artificial-intelligence/answers.html" }, { "number": 19, "label": "Computational thinking and problem-solving", "slug": "9618-topic-19-computational-thinking-and-problem-solving", "questions_html": "9618-topic-19-computational-thinking-and-problem-solving/questions.html", "answers_html": "9618-topic-19-computational-thinking-and-problem-solving/answers.html" }, { "number": 20, "label": "Further programming", "slug": "9618-topic-20-further-programming", "questions_html": "9618-topic-20-further-programming/questions.html", "answers_html": "9618-topic-20-further-programming/answers.html" }, { "number": null, "label": "Practical programming", "slug": "9618-practical-programming", "questions_html": "9618-practical-programming/questions.html", "answers_html": "9618-practical-programming/answers.html" } ], "papers": [ { "year": 2021, "session": "May/June", "session_code": "mj", "variant": "31", "paper": 3, "question_count": 9, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "local_path": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf" }, { "year": 2021, "session": "May/June", "session_code": "mj", "variant": "32", "paper": 3, "question_count": 9, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "local_path": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf" }, { "year": 2021, "session": "May/June", "session_code": "mj", "variant": "33", "paper": 3, "question_count": 9, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "local_path": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf" }, { "year": 2021, "session": "May/June", "session_code": "mj", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_41.pdf?download=true", "local_path": "_source-pdfs/2021-may-june/qp/9618_s21_qp_41.pdf" }, { "year": 2021, "session": "May/June", "session_code": "mj", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_42.pdf?download=true", "local_path": "_source-pdfs/2021-may-june/qp/9618_s21_qp_42.pdf" }, { "year": 2021, "session": "May/June", "session_code": "mj", "variant": "43", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_43.pdf?download=true", "local_path": "_source-pdfs/2021-may-june/qp/9618_s21_qp_43.pdf" }, { "year": 2021, "session": "Oct/Nov", "session_code": "on", "variant": "31", "paper": 3, "question_count": 10, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "local_path": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf" }, { "year": 2021, "session": "Oct/Nov", "session_code": "on", "variant": "32", "paper": 3, "question_count": 10, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "local_path": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf" }, { "year": 2021, "session": "Oct/Nov", "session_code": "on", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_41.pdf?download=true", "local_path": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_41.pdf" }, { "year": 2021, "session": "Oct/Nov", "session_code": "on", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_42.pdf?download=true", "local_path": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_42.pdf" }, { "year": 2022, "session": "May/June", "session_code": "mj", "variant": "31", "paper": 3, "question_count": 9, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "local_path": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf" }, { "year": 2022, "session": "May/June", "session_code": "mj", "variant": "32", "paper": 3, "question_count": 9, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_32.pdf?download=true", "local_path": "_source-pdfs/2022-may-june/qp/9618_s22_qp_32.pdf" }, { "year": 2022, "session": "May/June", "session_code": "mj", "variant": "33", "paper": 3, "question_count": 9, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_33.pdf?download=true", "local_path": "_source-pdfs/2022-may-june/qp/9618_s22_qp_33.pdf" }, { "year": 2022, "session": "May/June", "session_code": "mj", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_41.pdf?download=true", "local_path": "_source-pdfs/2022-may-june/qp/9618_s22_qp_41.pdf" }, { "year": 2022, "session": "May/June", "session_code": "mj", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_42.pdf?download=true", "local_path": "_source-pdfs/2022-may-june/qp/9618_s22_qp_42.pdf" }, { "year": 2022, "session": "May/June", "session_code": "mj", "variant": "43", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_43.pdf?download=true", "local_path": "_source-pdfs/2022-may-june/qp/9618_s22_qp_43.pdf" }, { "year": 2022, "session": "Oct/Nov", "session_code": "on", "variant": "31", "paper": 3, "question_count": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-Oct-Nov/9618_w22_qp_31.pdf?download=true", "local_path": "_source-pdfs/2022-oct-nov/qp/9618_w22_qp_31.pdf" }, { "year": 2022, "session": "Oct/Nov", "session_code": "on", "variant": "32", "paper": 3, "question_count": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-Oct-Nov/9618_w22_qp_32.pdf?download=true", "local_path": "_source-pdfs/2022-oct-nov/qp/9618_w22_qp_32.pdf" }, { "year": 2022, "session": "Oct/Nov", "session_code": "on", "variant": "33", "paper": 3, "question_count": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-Oct-Nov/9618_w22_qp_33.pdf?download=true", "local_path": "_source-pdfs/2022-oct-nov/qp/9618_w22_qp_33.pdf" }, { "year": 2022, "session": "Oct/Nov", "session_code": "on", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-Oct-Nov/9618_w22_qp_41.pdf?download=true", "local_path": "_source-pdfs/2022-oct-nov/qp/9618_w22_qp_41.pdf" }, { "year": 2022, "session": "Oct/Nov", "session_code": "on", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-Oct-Nov/9618_w22_qp_42.pdf?download=true", "local_path": "_source-pdfs/2022-oct-nov/qp/9618_w22_qp_42.pdf" }, { "year": 2022, "session": "Oct/Nov", "session_code": "on", "variant": "43", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-Oct-Nov/9618_w22_qp_43.pdf?download=true", "local_path": "_source-pdfs/2022-oct-nov/qp/9618_w22_qp_43.pdf" }, { "year": 2023, "session": "May/June", "session_code": "mj", "variant": "31", "paper": 3, "question_count": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-May-June/9618_s23_qp_31.pdf?download=true", "local_path": "_source-pdfs/2023-may-june/qp/9618_s23_qp_31.pdf" }, { "year": 2023, "session": "May/June", "session_code": "mj", "variant": "32", "paper": 3, "question_count": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-May-June/9618_s23_qp_32.pdf?download=true", "local_path": "_source-pdfs/2023-may-june/qp/9618_s23_qp_32.pdf" }, { "year": 2023, "session": "May/June", "session_code": "mj", "variant": "33", "paper": 3, "question_count": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-May-June/9618_s23_qp_33.pdf?download=true", "local_path": "_source-pdfs/2023-may-june/qp/9618_s23_qp_33.pdf" }, { "year": 2023, "session": "May/June", "session_code": "mj", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-May-June/9618_s23_qp_41.pdf?download=true", "local_path": "_source-pdfs/2023-may-june/qp/9618_s23_qp_41.pdf" }, { "year": 2023, "session": "May/June", "session_code": "mj", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-May-June/9618_s23_qp_42.pdf?download=true", "local_path": "_source-pdfs/2023-may-june/qp/9618_s23_qp_42.pdf" }, { "year": 2023, "session": "May/June", "session_code": "mj", "variant": "43", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-May-June/9618_s23_qp_43.pdf?download=true", "local_path": "_source-pdfs/2023-may-june/qp/9618_s23_qp_43.pdf" }, { "year": 2023, "session": "Oct/Nov", "session_code": "on", "variant": "31", "paper": 3, "question_count": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-Oct-Nov/9618_w23_qp_31.pdf?download=true", "local_path": "_source-pdfs/2023-oct-nov/qp/9618_w23_qp_31.pdf" }, { "year": 2023, "session": "Oct/Nov", "session_code": "on", "variant": "32", "paper": 3, "question_count": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-Oct-Nov/9618_w23_qp_32.pdf?download=true", "local_path": "_source-pdfs/2023-oct-nov/qp/9618_w23_qp_32.pdf" }, { "year": 2023, "session": "Oct/Nov", "session_code": "on", "variant": "33", "paper": 3, "question_count": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-Oct-Nov/9618_w23_qp_33.pdf?download=true", "local_path": "_source-pdfs/2023-oct-nov/qp/9618_w23_qp_33.pdf" }, { "year": 2023, "session": "Oct/Nov", "session_code": "on", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-Oct-Nov/9618_w23_qp_41.pdf?download=true", "local_path": "_source-pdfs/2023-oct-nov/qp/9618_w23_qp_41.pdf" }, { "year": 2023, "session": "Oct/Nov", "session_code": "on", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-Oct-Nov/9618_w23_qp_42.pdf?download=true", "local_path": "_source-pdfs/2023-oct-nov/qp/9618_w23_qp_42.pdf" }, { "year": 2023, "session": "Oct/Nov", "session_code": "on", "variant": "43", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2023-Oct-Nov/9618_w23_qp_43.pdf?download=true", "local_path": "_source-pdfs/2023-oct-nov/qp/9618_w23_qp_43.pdf" }, { "year": 2024, "session": "May/June", "session_code": "mj", "variant": "31", "paper": 3, "question_count": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-May-June/9618_s24_qp_31.pdf?download=true", "local_path": "_source-pdfs/2024-may-june/qp/9618_s24_qp_31.pdf" }, { "year": 2024, "session": "May/June", "session_code": "mj", "variant": "32", "paper": 3, "question_count": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-May-June/9618_s24_qp_32.pdf?download=true", "local_path": "_source-pdfs/2024-may-june/qp/9618_s24_qp_32.pdf" }, { "year": 2024, "session": "May/June", "session_code": "mj", "variant": "33", "paper": 3, "question_count": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-May-June/9618_s24_qp_33.pdf?download=true", "local_path": "_source-pdfs/2024-may-june/qp/9618_s24_qp_33.pdf" }, { "year": 2024, "session": "May/June", "session_code": "mj", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-May-June/9618_s24_qp_41.pdf?download=true", "local_path": "_source-pdfs/2024-may-june/qp/9618_s24_qp_41.pdf" }, { "year": 2024, "session": "May/June", "session_code": "mj", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-May-June/9618_s24_qp_42.pdf?download=true", "local_path": "_source-pdfs/2024-may-june/qp/9618_s24_qp_42.pdf" }, { "year": 2024, "session": "May/June", "session_code": "mj", "variant": "43", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-May-June/9618_s24_qp_43.pdf?download=true", "local_path": "_source-pdfs/2024-may-june/qp/9618_s24_qp_43.pdf" }, { "year": 2024, "session": "Oct/Nov", "session_code": "on", "variant": "31", "paper": 3, "question_count": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-Oct-Nov/9618_w24_qp_31.pdf?download=true", "local_path": "_source-pdfs/2024-oct-nov/qp/9618_w24_qp_31.pdf" }, { "year": 2024, "session": "Oct/Nov", "session_code": "on", "variant": "32", "paper": 3, "question_count": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-Oct-Nov/9618_w24_qp_32.pdf?download=true", "local_path": "_source-pdfs/2024-oct-nov/qp/9618_w24_qp_32.pdf" }, { "year": 2024, "session": "Oct/Nov", "session_code": "on", "variant": "33", "paper": 3, "question_count": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-Oct-Nov/9618_w24_qp_33.pdf?download=true", "local_path": "_source-pdfs/2024-oct-nov/qp/9618_w24_qp_33.pdf" }, { "year": 2024, "session": "Oct/Nov", "session_code": "on", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-Oct-Nov/9618_w24_qp_41.pdf?download=true", "local_path": "_source-pdfs/2024-oct-nov/qp/9618_w24_qp_41.pdf" }, { "year": 2024, "session": "Oct/Nov", "session_code": "on", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-Oct-Nov/9618_w24_qp_42.pdf?download=true", "local_path": "_source-pdfs/2024-oct-nov/qp/9618_w24_qp_42.pdf" }, { "year": 2024, "session": "Oct/Nov", "session_code": "on", "variant": "43", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2024-Oct-Nov/9618_w24_qp_43.pdf?download=true", "local_path": "_source-pdfs/2024-oct-nov/qp/9618_w24_qp_43.pdf" }, { "year": 2025, "session": "May/June", "session_code": "mj", "variant": "31", "paper": 3, "question_count": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-May-June/9618_s25_qp_31.pdf?download=true", "local_path": "_source-pdfs/2025-may-june/qp/9618_s25_qp_31.pdf" }, { "year": 2025, "session": "May/June", "session_code": "mj", "variant": "32", "paper": 3, "question_count": 13, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-May-June/9618_s25_qp_32.pdf?download=true", "local_path": "_source-pdfs/2025-may-june/qp/9618_s25_qp_32.pdf" }, { "year": 2025, "session": "May/June", "session_code": "mj", "variant": "33", "paper": 3, "question_count": 13, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-May-June/9618_s25_qp_33.pdf?download=true", "local_path": "_source-pdfs/2025-may-june/qp/9618_s25_qp_33.pdf" }, { "year": 2025, "session": "May/June", "session_code": "mj", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-May-June/9618_s25_qp_41.pdf?download=true", "local_path": "_source-pdfs/2025-may-june/qp/9618_s25_qp_41.pdf" }, { "year": 2025, "session": "May/June", "session_code": "mj", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-May-June/9618_s25_qp_42.pdf?download=true", "local_path": "_source-pdfs/2025-may-june/qp/9618_s25_qp_42.pdf" }, { "year": 2025, "session": "May/June", "session_code": "mj", "variant": "43", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-May-June/9618_s25_qp_43.pdf?download=true", "local_path": "_source-pdfs/2025-may-june/qp/9618_s25_qp_43.pdf" }, { "year": 2025, "session": "Oct/Nov", "session_code": "on", "variant": "31", "paper": 3, "question_count": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-Oct-Nov/9618_w25_qp_31.pdf?download=true", "local_path": "_source-pdfs/2025-oct-nov/qp/9618_w25_qp_31.pdf" }, { "year": 2025, "session": "Oct/Nov", "session_code": "on", "variant": "32", "paper": 3, "question_count": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-Oct-Nov/9618_w25_qp_32.pdf?download=true", "local_path": "_source-pdfs/2025-oct-nov/qp/9618_w25_qp_32.pdf" }, { "year": 2025, "session": "Oct/Nov", "session_code": "on", "variant": "33", "paper": 3, "question_count": 13, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-Oct-Nov/9618_w25_qp_33.pdf?download=true", "local_path": "_source-pdfs/2025-oct-nov/qp/9618_w25_qp_33.pdf" }, { "year": 2025, "session": "Oct/Nov", "session_code": "on", "variant": "41", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-Oct-Nov/9618_w25_qp_41.pdf?download=true", "local_path": "_source-pdfs/2025-oct-nov/qp/9618_w25_qp_41.pdf" }, { "year": 2025, "session": "Oct/Nov", "session_code": "on", "variant": "42", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-Oct-Nov/9618_w25_qp_42.pdf?download=true", "local_path": "_source-pdfs/2025-oct-nov/qp/9618_w25_qp_42.pdf" }, { "year": 2025, "session": "Oct/Nov", "session_code": "on", "variant": "43", "paper": 4, "question_count": 3, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2025-Oct-Nov/9618_w25_qp_43.pdf?download=true", "local_path": "_source-pdfs/2025-oct-nov/qp/9618_w25_qp_43.pdf" } ], "records": [ { "id": "9618-2021-mj-31-q01", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 1, "topic_number": 13, "topic": "Data representation", "topic_slug": "9618-topic-13-data-representation", "marks": 14, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "source_pages": [ 2, 3 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf", "image_paths": [ "9618-topic-13-data-representation/assets/9618-2021-mj-31-q01-p01.png", "9618-topic-13-data-representation/assets/9618-2021-mj-31-q01-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-31-q01", "html": "9618-topic-13-data-representation/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_31.pdf?download=true", "source_pages": [ 3, 4 ], "marks": 14 }, "text_excerpt": "Real numbers are stored in a computer system using floating-point representation with: 1\n• 10 bits for the mantissa\n• 6 bits for the exponent\n• Two’s complement form for both the mantissa and the exponent.\nCalculate the normalised floating-point representation of –7.25 in this system. (a)\nShow your working.\nMantissa Exponent\nWorking .....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n[3]\nCalculate the denary value of the given binary floating-point number. (b)\nShow your working.\nMantissa Exponent\n1 0 1 1 0 0 0 1 1 1 0 0 0 1 1 1\nWorking .....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\nAnswer ......................................................................................................................................\n[3]\n© UCLES 2021 9618/31/M/J/21\n3\nThe given binary floating-point number is not normalised. (c)\nNormalise the floating-point number. Show your working.\nMantissa Exponent\n0 0 0 0 0 0 0 1 1 1 1 0 0 1 1 1\nMantissa Exponent\nWorking .....................................................................................................................................\n.............................................................................................................." }, { "id": "9618-2021-mj-31-q02", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 2, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "source_pages": [ 4 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2021-mj-31-q02-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-31-q02", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_31.pdf?download=true", "source_pages": [ 4 ], "marks": 8 }, "text_excerpt": "Describe the purpose of a user-defined data type. 2 (a)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nDefine, using pseudocode, the following enumerated data types: (b)\nto hold data about the days students are usually in school. (i)\nSchoolDay\n...........................................................................................................................................\n..................................................................................................................................... [1]\nto hold data about the days that are not school days. (ii)\nWeekEnd\n...........................................................................................................................................\n..................................................................................................................................... [1]\nDefine, using pseudocode, the composite data type . This will hold data about club (c)\nClubMeet\nmembers that includes:\n• first name and last name\n• the two days they attend:\n○ one on a school day\n○ one not on a school day.\nUse the enumerated types you created in (b). part\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n....................................................................................................................................." }, { "id": "9618-2021-mj-31-q03", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 3, "topic_number": 16, "topic": "System software", "topic_slug": "9618-topic-16-system-software", "marks": 9, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "source_pages": [ 5 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf", "image_paths": [ "9618-topic-16-system-software/assets/9618-2021-mj-31-q03-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-31-q03", "html": "9618-topic-16-system-software/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_31.pdf?download=true", "source_pages": [ 5 ], "marks": 9 }, "text_excerpt": "Draw line to connect each term to the 3 (a) one Operating System (OS) most appropriate\ndescription about it.\nOS term Description\nUsing secondary storage to simulate\nadditional main memory\nMulti-tasking\nManaging the processes running on\nthe CPU\nPaging\nManaging the execution of many programs\nthat appear to run at the same time\nInterrupt handling\nLocating non-contiguous blocks of data and\nrelocating them\nScheduling\nTransferring control to another routine when\na service is required\nVirtual memory\nReading/writing same-size blocks of data\nfrom/to secondary storage when required\n[5]\nExplain how an interpreter executes a program without producing a complete translated (b)\nversion of it.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [4]\n[Turn over © UCLES 2021 9618/31/M/J/21" }, { "id": "9618-2021-mj-31-q04", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 4, "topic_number": 16, "topic": "System software", "topic_slug": "9618-topic-16-system-software", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "source_pages": [ 6 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf", "image_paths": [ "9618-topic-16-system-software/assets/9618-2021-mj-31-q04-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-31-q04", "html": "9618-topic-16-system-software/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_31.pdf?download=true", "source_pages": [ 5, 6 ], "marks": 8 }, "text_excerpt": "Explain why Reverse Polish Notation (RPN) is used to carry out the evaluation of 4 (a) (i)\nexpressions.\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [2]\nIdentify, with reasons, a data structure that could be used to evaluate an expression (ii)\nin RPN.\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [2]\nWrite the infix expression in RPN. (b)\n(a – b) * (a + c) / 7\n...................................................................................................................................................\n............................................................................................................................................. [1]\nWrite the RPN expression as an infix expression. (c)\na b / 4 * a b + -\n...................................................................................................................................................\n............................................................................................................................................. [1]\nEvaluate the RPN expression: (d)\na b + c d / /\nwhere .\na = 17, b = 3, c = 48 and d = 12\nShow your working.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\n© UCLES 2021 9618/31/M/J/21" }, { "id": "9618-2021-mj-31-q05", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 5, "topic_number": 18, "topic": "Artificial intelligence (AI)", "topic_slug": "9618-topic-18-artificial-intelligence", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "source_pages": [ 7, 8 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf", "image_paths": [ "9618-topic-18-artificial-intelligence/assets/9618-2021-mj-31-q05-p01.png", "9618-topic-18-artificial-intelligence/assets/9618-2021-mj-31-q05-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-31-q05", "html": "9618-topic-18-artificial-intelligence/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_31.pdf?download=true", "source_pages": [ 6, 7 ], "marks": 8 }, "text_excerpt": "Calculate the shortest distance between the base and each of the other towns in the diagram 5 (a)\nusing Dijkstra’s algorithm.\nShow your working write your answers in the table provided. and\nBase\n4\n5\nTown 1 2\nTown 2\n1\n8\nTown 3\n7 3 Town 6\n1\n5\n6\nTown 5 Town 4\nWorking .....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\nAnswers\nTown 1 Town 2 Town 3 Town 4 Town 5 Town 6\n[5]\n[Turn over © UCLES 2021 9618/31/M/J/21\n8\nExplain the use of graphs to aid Artificial Intelligence (AI). (b)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [3]" }, { "id": "9618-2021-mj-31-q06", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 6, "topic_number": 14, "topic": "Communication and internet technologies", "topic_slug": "9618-topic-14-communication-and-internet-technologies", "marks": 4, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "source_pages": [ 8 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf", "image_paths": [ "9618-topic-14-communication-and-internet-technologies/assets/9618-2021-mj-31-q06-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-31-q06", "html": "9618-topic-14-communication-and-internet-technologies/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_31.pdf?download=true", "source_pages": [ 7 ], "marks": 4 }, "text_excerpt": "Give benefits drawbacks of packet switching. 6 two and two\nBenefit 1 ...........................................................................................................................................\n..........................................................................................................................................................\nBenefit 2 ...........................................................................................................................................\n..........................................................................................................................................................\nDrawback 1 ......................................................................................................................................\n..........................................................................................................................................................\nDrawback 2 ......................................................................................................................................\n..........................................................................................................................................................\n[4]\n© UCLES 2021 9618/31/M/J/21" }, { "id": "9618-2021-mj-31-q07", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 7, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "source_pages": [ 9 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-mj-31-q07-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-31-q07", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_31.pdf?download=true", "source_pages": [ 8 ], "marks": 8 }, "text_excerpt": "The diagram shows a logic circuit. 7\nA P\nY\nB\nR C\nZ\nQ\nComplete the truth table for the given logic circuit. Show your working. (a)\nInputs Working space Outputs\nA B C P Q R Y Z\n0 0 0\n0 0 1\n0 1 0\n0 1 1\n1 0 0\n1 0 1\n1 1 0\n1 1 1\n[3]\nState the name of the logic circuit. (b)\n............................................................................................................................................. [1]\nWrite the Boolean expressions for the two outputs and in the truth table as (c) Y Z\nsum-of-products state the purpose of each output. and\n= ............................................................................................................................................ Y\nPurpose ....................................................................................................................................\n= ............................................................................................................................................ Z\nPurpose ....................................................................................................................................\n[4]\n[Turn over © UCLES 2021 9618/31/M/J/21" }, { "id": "9618-2021-mj-31-q08", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 8, "topic_number": 19, "topic": "Computational thinking and problem-solving", "topic_slug": "9618-topic-19-computational-thinking-and-problem-solving", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "source_pages": [ 10, 11 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf", "image_paths": [ "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-mj-31-q08-p01.png", "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-mj-31-q08-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-31-q08", "html": "9618-topic-19-computational-thinking-and-problem-solving/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_31.pdf?download=true", "source_pages": [ 8, 9 ], "marks": 8 }, "text_excerpt": "State factors that may affect the performance of a sorting algorithm. 8 (a) two\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nThe given algorithm is a simple bubble sort that arranges a set of scores stored in a one- (b)\ndimensional array into order, and orders the corresponding students’ names descending\nstored into a two-dimensional array in the same order as the scores. All the arrays are indexed\nfrom 1.\nThe contents of both arrays after sorting are shown.\nName\nScore\n1 2\n98 Smithfield Tom 1 1\n97 Johnson Jane 2 2\n… …\n5 Peters Jade 248 248\n3 Allen John 249 249\n←\n249 YearSize\n←\nTRUE Flag\nWHILE Flag = TRUE\n←\nFALSE Flag\n←\n1 TO YearSize - 1 FOR Student\nIF Score[Student] < Score[Student + 1] THEN\n←\nScore[Student] Temp1\n←\nName[Student,1] Temp2\n←\nName[Student,2] Temp3\n←\nScore[Student + 1] Score[Student]\n←\nName[Student + 1,1] Name[Student,1]\n←\nName[Student + 1,2] Name[Student,2]\n←\nTemp1 Score[Student + 1]\n←\nTemp2 Name[Student + 1,1]\n←\nTemp3 Name[Student + 1,2]\n←\nTRUE Flag\nENDIF\nNEXT Student\nENDWHILE\n© UCLES 2021 9618/31/M/J/21\n11\nWrite an algorithm, using pseudocode, that will perform the same task using an insertion sort.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n.........................................................................................................................................." }, { "id": "9618-2021-mj-31-q09", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 9, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_31.pdf?download=true", "source_pages": [ 12 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_31.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2021-mj-31-q09-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-31-q09", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_31.pdf?download=true", "source_pages": [ 9, 10 ], "marks": 8 }, "text_excerpt": "Describe what is meant by programming language. 9 (a) an imperative (procedural)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nDescribe what is meant by programming language. (b) a declarative\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nIdentify the programming paradigm for each of these program code examples. (c)\nProgram code example Programming paradigm\nmale(john).\nfemale(ethel).\nparent(john, ethel).\nFOR Counter = 1 TO 20\nX = X * Counter\nNEXT Counter\nStart: LDD Counter\nINC ACC\nSTO Counter\npublic class Vehicle\n{\nprivate speed;\npublic Vehicle()\n{\nspeed = 0;\n}\n}\n[4]\nPermission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every\nreasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the\npublisher will be pleased to make amends at the earliest possible opportunity.\nTo avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge\nAssessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download\nat www.cambridgeinternational.org after the live examination series.\nCambridge Assessment International Education is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of the University of\nCambridge Local Examinations Syndicate (UCLES), which itself is a department of the University of Cambridge.\n© UCLES 2021 9618/31/M/J/21" }, { "id": "9618-2021-mj-32-q01", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "32", "question_number": 1, "topic_number": 13, "topic": "Data representation", "topic_slug": "9618-topic-13-data-representation", "marks": 14, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "source_pages": [ 2, 3 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf", "image_paths": [ "9618-topic-13-data-representation/assets/9618-2021-mj-32-q01-p01.png", "9618-topic-13-data-representation/assets/9618-2021-mj-32-q01-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-32-q01", "html": "9618-topic-13-data-representation/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_32.pdf?download=true", "source_pages": [ 3, 4 ], "marks": 14 }, "text_excerpt": "Real numbers are stored in a computer system using floating-point representation with: 1\n• 10 bits for the mantissa\n• 6 bits for the exponent\n• Two’s complement form for both the mantissa and the exponent.\nCalculate the normalised floating-point representation of –7.25 in this system. (a)\nShow your working.\nMantissa Exponent\nWorking .....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n[3]\nCalculate the denary value of the given binary floating-point number. (b)\nShow your working.\nMantissa Exponent\n1 0 1 1 0 0 0 1 1 1 0 0 0 1 1 1\nWorking .....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\nAnswer ......................................................................................................................................\n[3]\n© UCLES 2021 9618/32/M/J/21\n3\nThe given binary floating-point number is not normalised. (c)\nNormalise the floating-point number. Show your working.\nMantissa Exponent\n0 0 0 0 0 0 0 1 1 1 1 0 0 1 1 1\nMantissa Exponent\nWorking .....................................................................................................................................\n.............................................................................................................." }, { "id": "9618-2021-mj-32-q02", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "32", "question_number": 2, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "source_pages": [ 4 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2021-mj-32-q02-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-32-q02", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_32.pdf?download=true", "source_pages": [ 4 ], "marks": 8 }, "text_excerpt": "Describe the purpose of a user-defined data type. 2 (a)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nDefine, using pseudocode, the following enumerated data types: (b)\nto hold data about the days students are usually in school. (i)\nSchoolDay\n...........................................................................................................................................\n..................................................................................................................................... [1]\nto hold data about the days that are not school days. (ii)\nWeekEnd\n...........................................................................................................................................\n..................................................................................................................................... [1]\nDefine, using pseudocode, the composite data type . This will hold data about club (c)\nClubMeet\nmembers that includes:\n• first name and last name\n• the two days they attend:\n○ one on a school day\n○ one not on a school day.\nUse the enumerated types you created in (b). part\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n....................................................................................................................................." }, { "id": "9618-2021-mj-32-q03", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "32", "question_number": 3, "topic_number": 16, "topic": "System software", "topic_slug": "9618-topic-16-system-software", "marks": 9, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "source_pages": [ 5 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf", "image_paths": [ "9618-topic-16-system-software/assets/9618-2021-mj-32-q03-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-32-q03", "html": "9618-topic-16-system-software/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_32.pdf?download=true", "source_pages": [ 5 ], "marks": 9 }, "text_excerpt": "Draw line to connect each term to the 3 (a) one Operating System (OS) most appropriate\ndescription about it.\nOS term Description\nUsing secondary storage to simulate\nadditional main memory\nMulti-tasking\nManaging the processes running on\nthe CPU\nPaging\nManaging the execution of many programs\nthat appear to run at the same time\nInterrupt handling\nLocating non-contiguous blocks of data and\nrelocating them\nScheduling\nTransferring control to another routine when\na service is required\nVirtual memory\nReading/writing same-size blocks of data\nfrom/to secondary storage when required\n[5]\nExplain how an interpreter executes a program without producing a complete translated (b)\nversion of it.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [4]\n[Turn over © UCLES 2021 9618/32/M/J/21" }, { "id": "9618-2021-mj-32-q04", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "32", "question_number": 4, "topic_number": 16, "topic": "System software", "topic_slug": "9618-topic-16-system-software", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "source_pages": [ 6 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf", "image_paths": [ "9618-topic-16-system-software/assets/9618-2021-mj-32-q04-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-32-q04", "html": "9618-topic-16-system-software/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_32.pdf?download=true", "source_pages": [ 5, 6 ], "marks": 8 }, "text_excerpt": "Explain why Reverse Polish Notation (RPN) is used to carry out the evaluation of 4 (a) (i)\nexpressions.\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [2]\nIdentify, with reasons, a data structure that could be used to evaluate an expression (ii)\nin RPN.\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [2]\nWrite the infix expression in RPN. (b)\n(a – b) * (a + c) / 7\n...................................................................................................................................................\n............................................................................................................................................. [1]\nWrite the RPN expression as an infix expression. (c)\na b / 4 * a b + -\n...................................................................................................................................................\n............................................................................................................................................. [1]\nEvaluate the RPN expression: (d)\na b + c d / /\nwhere .\na = 17, b = 3, c = 48 and d = 12\nShow your working.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\n© UCLES 2021 9618/32/M/J/21" }, { "id": "9618-2021-mj-32-q05", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "32", "question_number": 5, "topic_number": 18, "topic": "Artificial intelligence (AI)", "topic_slug": "9618-topic-18-artificial-intelligence", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "source_pages": [ 7, 8 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf", "image_paths": [ "9618-topic-18-artificial-intelligence/assets/9618-2021-mj-32-q05-p01.png", "9618-topic-18-artificial-intelligence/assets/9618-2021-mj-32-q05-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-32-q05", "html": "9618-topic-18-artificial-intelligence/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_32.pdf?download=true", "source_pages": [ 6, 7 ], "marks": 8 }, "text_excerpt": "Calculate the shortest distance between the base and each of the other towns in the diagram 5 (a)\nusing Dijkstra’s algorithm.\nShow your working write your answers in the table provided. and\nBase\n4\n5\nTown 1 2\nTown 2\n1\n8\nTown 3\n7 3 Town 6\n1\n5\n6\nTown 5 Town 4\nWorking .....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\nAnswers\nTown 1 Town 2 Town 3 Town 4 Town 5 Town 6\n[5]\n[Turn over © UCLES 2021 9618/32/M/J/21\n8\nExplain the use of graphs to aid Artificial Intelligence (AI). (b)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [3]" }, { "id": "9618-2021-mj-32-q06", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "32", "question_number": 6, "topic_number": 14, "topic": "Communication and internet technologies", "topic_slug": "9618-topic-14-communication-and-internet-technologies", "marks": 4, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "source_pages": [ 8 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf", "image_paths": [ "9618-topic-14-communication-and-internet-technologies/assets/9618-2021-mj-32-q06-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-32-q06", "html": "9618-topic-14-communication-and-internet-technologies/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_32.pdf?download=true", "source_pages": [ 7 ], "marks": 4 }, "text_excerpt": "Give benefits drawbacks of packet switching. 6 two and two\nBenefit 1 ...........................................................................................................................................\n..........................................................................................................................................................\nBenefit 2 ...........................................................................................................................................\n..........................................................................................................................................................\nDrawback 1 ......................................................................................................................................\n..........................................................................................................................................................\nDrawback 2 ......................................................................................................................................\n..........................................................................................................................................................\n[4]\n© UCLES 2021 9618/32/M/J/21" }, { "id": "9618-2021-mj-32-q07", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "32", "question_number": 7, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "source_pages": [ 9 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-mj-32-q07-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-32-q07", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_32.pdf?download=true", "source_pages": [ 8 ], "marks": 8 }, "text_excerpt": "The diagram shows a logic circuit. 7\nA P\nY\nB\nR C\nZ\nQ\nComplete the truth table for the given logic circuit. Show your working. (a)\nInputs Working space Outputs\nA B C P Q R Y Z\n0 0 0\n0 0 1\n0 1 0\n0 1 1\n1 0 0\n1 0 1\n1 1 0\n1 1 1\n[3]\nState the name of the logic circuit. (b)\n............................................................................................................................................. [1]\nWrite the Boolean expressions for the two outputs and in the truth table as (c) Y Z\nsum-of-products state the purpose of each output. and\n= ............................................................................................................................................ Y\nPurpose ....................................................................................................................................\n= ............................................................................................................................................ Z\nPurpose ....................................................................................................................................\n[4]\n[Turn over © UCLES 2021 9618/32/M/J/21" }, { "id": "9618-2021-mj-32-q08", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "32", "question_number": 8, "topic_number": 19, "topic": "Computational thinking and problem-solving", "topic_slug": "9618-topic-19-computational-thinking-and-problem-solving", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "source_pages": [ 10, 11 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf", "image_paths": [ "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-mj-32-q08-p01.png", "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-mj-32-q08-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-32-q08", "html": "9618-topic-19-computational-thinking-and-problem-solving/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_32.pdf?download=true", "source_pages": [ 8, 9 ], "marks": 8 }, "text_excerpt": "State factors that may affect the performance of a sorting algorithm. 8 (a) two\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nThe given algorithm is a simple bubble sort that arranges a set of scores stored in a one- (b)\ndimensional array into order, and orders the corresponding students’ names descending\nstored into a two-dimensional array in the same order as the scores. All the arrays are indexed\nfrom 1.\nThe contents of both arrays after sorting are shown.\nName\nScore\n1 2\n98 Smithfield Tom 1 1\n97 Johnson Jane 2 2\n… …\n5 Peters Jade 248 248\n3 Allen John 249 249\n←\n249 YearSize\n←\nTRUE Flag\nWHILE Flag = TRUE\n←\nFALSE Flag\n←\n1 TO YearSize - 1 FOR Student\nIF Score[Student] < Score[Student + 1] THEN\n←\nScore[Student] Temp1\n←\nName[Student,1] Temp2\n←\nName[Student,2] Temp3\n←\nScore[Student + 1] Score[Student]\n←\nName[Student + 1,1] Name[Student,1]\n←\nName[Student + 1,2] Name[Student,2]\n←\nTemp1 Score[Student + 1]\n←\nTemp2 Name[Student + 1,1]\n←\nTemp3 Name[Student + 1,2]\n←\nTRUE Flag\nENDIF\nNEXT Student\nENDWHILE\n© UCLES 2021 9618/32/M/J/21\n11\nWrite an algorithm, using pseudocode, that will perform the same task using an insertion sort.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n.........................................................................................................................................." }, { "id": "9618-2021-mj-32-q09", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "32", "question_number": 9, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_32.pdf?download=true", "source_pages": [ 12 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_32.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2021-mj-32-q09-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-32-q09", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_32.pdf?download=true", "source_pages": [ 9, 10 ], "marks": 8 }, "text_excerpt": "Describe what is meant by programming language. 9 (a) an imperative (procedural)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nDescribe what is meant by programming language. (b) a declarative\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nIdentify the programming paradigm for each of these program code examples. (c)\nProgram code example Programming paradigm\nmale(john).\nfemale(ethel).\nparent(john, ethel).\nFOR Counter = 1 TO 20\nX = X * Counter\nNEXT Counter\nStart: LDD Counter\nINC ACC\nSTO Counter\npublic class Vehicle\n{\nprivate speed;\npublic Vehicle()\n{\nspeed = 0;\n}\n}\n[4]\nPermission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every\nreasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the\npublisher will be pleased to make amends at the earliest possible opportunity.\nTo avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge\nAssessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download\nat www.cambridgeinternational.org after the live examination series.\nCambridge Assessment International Education is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of the University of\nCambridge Local Examinations Syndicate (UCLES), which itself is a department of the University of Cambridge.\n© UCLES 2021 9618/32/M/J/21" }, { "id": "9618-2021-mj-33-q01", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "33", "question_number": 1, "topic_number": 13, "topic": "Data representation", "topic_slug": "9618-topic-13-data-representation", "marks": 14, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "source_pages": [ 2, 3 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf", "image_paths": [ "9618-topic-13-data-representation/assets/9618-2021-mj-33-q01-p01.png", "9618-topic-13-data-representation/assets/9618-2021-mj-33-q01-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-33-q01", "html": "9618-topic-13-data-representation/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_33.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_33.pdf?download=true", "source_pages": [ 3, 4 ], "marks": 14 }, "text_excerpt": "Real numbers are stored in a computer system using floating-point representation with: 1\n• 10 bits for the mantissa\n• 6 bits for the exponent\n• Two’s complement form for both the mantissa and the exponent.\nCalculate the normalised floating-point representation of –7.25 in this system. (a)\nShow your working.\nMantissa Exponent\nWorking .....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n[3]\nCalculate the denary value of the given binary floating-point number. (b)\nShow your working.\nMantissa Exponent\n1 0 1 1 0 0 0 1 1 1 0 0 0 1 1 1\nWorking .....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\nAnswer ......................................................................................................................................\n[3]\n© UCLES 2021 9618/33/M/J/21\n3\nThe given binary floating-point number is not normalised. (c)\nNormalise the floating-point number. Show your working.\nMantissa Exponent\n0 0 0 0 0 0 0 1 1 1 1 0 0 1 1 1\nMantissa Exponent\nWorking .....................................................................................................................................\n.............................................................................................................." }, { "id": "9618-2021-mj-33-q02", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "33", "question_number": 2, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "source_pages": [ 4 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2021-mj-33-q02-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-33-q02", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_33.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_33.pdf?download=true", "source_pages": [ 4 ], "marks": 8 }, "text_excerpt": "Describe the purpose of a user-defined data type. 2 (a)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nDefine, using pseudocode, the following enumerated data types: (b)\nto hold data about the days students are usually in school. (i)\nSchoolDay\n...........................................................................................................................................\n..................................................................................................................................... [1]\nto hold data about the days that are not school days. (ii)\nWeekEnd\n...........................................................................................................................................\n..................................................................................................................................... [1]\nDefine, using pseudocode, the composite data type . This will hold data about club (c)\nClubMeet\nmembers that includes:\n• first name and last name\n• the two days they attend:\n○ one on a school day\n○ one not on a school day.\nUse the enumerated types you created in (b). part\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n....................................................................................................................................." }, { "id": "9618-2021-mj-33-q03", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "33", "question_number": 3, "topic_number": 16, "topic": "System software", "topic_slug": "9618-topic-16-system-software", "marks": 9, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "source_pages": [ 5 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf", "image_paths": [ "9618-topic-16-system-software/assets/9618-2021-mj-33-q03-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-33-q03", "html": "9618-topic-16-system-software/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_33.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_33.pdf?download=true", "source_pages": [ 5 ], "marks": 9 }, "text_excerpt": "Draw line to connect each term to the 3 (a) one Operating System (OS) most appropriate\ndescription about it.\nOS term Description\nUsing secondary storage to simulate\nadditional main memory\nMulti-tasking\nManaging the processes running on\nthe CPU\nPaging\nManaging the execution of many programs\nthat appear to run at the same time\nInterrupt handling\nLocating non-contiguous blocks of data and\nrelocating them\nScheduling\nTransferring control to another routine when\na service is required\nVirtual memory\nReading/writing same-size blocks of data\nfrom/to secondary storage when required\n[5]\nExplain how an interpreter executes a program without producing a complete translated (b)\nversion of it.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [4]\n[Turn over © UCLES 2021 9618/33/M/J/21" }, { "id": "9618-2021-mj-33-q04", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "33", "question_number": 4, "topic_number": 16, "topic": "System software", "topic_slug": "9618-topic-16-system-software", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "source_pages": [ 6 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf", "image_paths": [ "9618-topic-16-system-software/assets/9618-2021-mj-33-q04-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-33-q04", "html": "9618-topic-16-system-software/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_33.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_33.pdf?download=true", "source_pages": [ 5, 6 ], "marks": 8 }, "text_excerpt": "Explain why Reverse Polish Notation (RPN) is used to carry out the evaluation of 4 (a) (i)\nexpressions.\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [2]\nIdentify, with reasons, a data structure that could be used to evaluate an expression (ii)\nin RPN.\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [2]\nWrite the infix expression in RPN. (b)\n(a – b) * (a + c) / 7\n...................................................................................................................................................\n............................................................................................................................................. [1]\nWrite the RPN expression as an infix expression. (c)\na b / 4 * a b + -\n...................................................................................................................................................\n............................................................................................................................................. [1]\nEvaluate the RPN expression: (d)\na b + c d / /\nwhere .\na = 17, b = 3, c = 48 and d = 12\nShow your working.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\n© UCLES 2021 9618/33/M/J/21" }, { "id": "9618-2021-mj-33-q05", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "33", "question_number": 5, "topic_number": 18, "topic": "Artificial intelligence (AI)", "topic_slug": "9618-topic-18-artificial-intelligence", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "source_pages": [ 7, 8 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf", "image_paths": [ "9618-topic-18-artificial-intelligence/assets/9618-2021-mj-33-q05-p01.png", "9618-topic-18-artificial-intelligence/assets/9618-2021-mj-33-q05-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-33-q05", "html": "9618-topic-18-artificial-intelligence/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_33.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_33.pdf?download=true", "source_pages": [ 6, 7 ], "marks": 8 }, "text_excerpt": "Calculate the shortest distance between the base and each of the other towns in the diagram 5 (a)\nusing Dijkstra’s algorithm.\nShow your working write your answers in the table provided. and\nBase\n4\n5\nTown 1 2\nTown 2\n1\n8\nTown 3\n7 3 Town 6\n1\n5\n6\nTown 5 Town 4\nWorking .....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\nAnswers\nTown 1 Town 2 Town 3 Town 4 Town 5 Town 6\n[5]\n[Turn over © UCLES 2021 9618/33/M/J/21\n8\nExplain the use of graphs to aid Artificial Intelligence (AI). (b)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [3]" }, { "id": "9618-2021-mj-33-q06", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "33", "question_number": 6, "topic_number": 14, "topic": "Communication and internet technologies", "topic_slug": "9618-topic-14-communication-and-internet-technologies", "marks": 4, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "source_pages": [ 8 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf", "image_paths": [ "9618-topic-14-communication-and-internet-technologies/assets/9618-2021-mj-33-q06-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-33-q06", "html": "9618-topic-14-communication-and-internet-technologies/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_33.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_33.pdf?download=true", "source_pages": [ 7 ], "marks": 4 }, "text_excerpt": "Give benefits drawbacks of packet switching. 6 two and two\nBenefit 1 ...........................................................................................................................................\n..........................................................................................................................................................\nBenefit 2 ...........................................................................................................................................\n..........................................................................................................................................................\nDrawback 1 ......................................................................................................................................\n..........................................................................................................................................................\nDrawback 2 ......................................................................................................................................\n..........................................................................................................................................................\n[4]\n© UCLES 2021 9618/33/M/J/21" }, { "id": "9618-2021-mj-33-q07", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "33", "question_number": 7, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "source_pages": [ 9 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-mj-33-q07-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-33-q07", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_33.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_33.pdf?download=true", "source_pages": [ 8 ], "marks": 8 }, "text_excerpt": "The diagram shows a logic circuit. 7\nA P\nY\nB\nR C\nZ\nQ\nComplete the truth table for the given logic circuit. Show your working. (a)\nInputs Working space Outputs\nA B C P Q R Y Z\n0 0 0\n0 0 1\n0 1 0\n0 1 1\n1 0 0\n1 0 1\n1 1 0\n1 1 1\n[3]\nState the name of the logic circuit. (b)\n............................................................................................................................................. [1]\nWrite the Boolean expressions for the two outputs and in the truth table as (c) Y Z\nsum-of-products state the purpose of each output. and\n= ............................................................................................................................................ Y\nPurpose ....................................................................................................................................\n= ............................................................................................................................................ Z\nPurpose ....................................................................................................................................\n[4]\n[Turn over © UCLES 2021 9618/33/M/J/21" }, { "id": "9618-2021-mj-33-q08", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "33", "question_number": 8, "topic_number": 19, "topic": "Computational thinking and problem-solving", "topic_slug": "9618-topic-19-computational-thinking-and-problem-solving", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "source_pages": [ 10, 11 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf", "image_paths": [ "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-mj-33-q08-p01.png", "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-mj-33-q08-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-33-q08", "html": "9618-topic-19-computational-thinking-and-problem-solving/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_33.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_33.pdf?download=true", "source_pages": [ 8, 9 ], "marks": 8 }, "text_excerpt": "State factors that may affect the performance of a sorting algorithm. 8 (a) two\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nThe given algorithm is a simple bubble sort that arranges a set of scores stored in a one- (b)\ndimensional array into order, and orders the corresponding students’ names descending\nstored into a two-dimensional array in the same order as the scores. All the arrays are indexed\nfrom 1.\nThe contents of both arrays after sorting are shown.\nName\nScore\n1 2\n98 Smithfield Tom 1 1\n97 Johnson Jane 2 2\n… …\n5 Peters Jade 248 248\n3 Allen John 249 249\n←\n249 YearSize\n←\nTRUE Flag\nWHILE Flag = TRUE\n←\nFALSE Flag\n←\n1 TO YearSize - 1 FOR Student\nIF Score[Student] < Score[Student + 1] THEN\n←\nScore[Student] Temp1\n←\nName[Student,1] Temp2\n←\nName[Student,2] Temp3\n←\nScore[Student + 1] Score[Student]\n←\nName[Student + 1,1] Name[Student,1]\n←\nName[Student + 1,2] Name[Student,2]\n←\nTemp1 Score[Student + 1]\n←\nTemp2 Name[Student + 1,1]\n←\nTemp3 Name[Student + 1,2]\n←\nTRUE Flag\nENDIF\nNEXT Student\nENDWHILE\n© UCLES 2021 9618/33/M/J/21\n11\nWrite an algorithm, using pseudocode, that will perform the same task using an insertion sort.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n.........................................................................................................................................." }, { "id": "9618-2021-mj-33-q09", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "33", "question_number": 9, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_33.pdf?download=true", "source_pages": [ 12 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_33.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2021-mj-33-q09-p01.png" ], "answer": { "status": "available", "id": "9618-2021-mj-33-q09", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_33.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_33.pdf?download=true", "source_pages": [ 9, 10 ], "marks": 8 }, "text_excerpt": "Describe what is meant by programming language. 9 (a) an imperative (procedural)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nDescribe what is meant by programming language. (b) a declarative\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nIdentify the programming paradigm for each of these program code examples. (c)\nProgram code example Programming paradigm\nmale(john).\nfemale(ethel).\nparent(john, ethel).\nFOR Counter = 1 TO 20\nX = X * Counter\nNEXT Counter\nStart: LDD Counter\nINC ACC\nSTO Counter\npublic class Vehicle\n{\nprivate speed;\npublic Vehicle()\n{\nspeed = 0;\n}\n}\n[4]\nPermission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every\nreasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the\npublisher will be pleased to make amends at the earliest possible opportunity.\nTo avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge\nAssessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download\nat www.cambridgeinternational.org after the live examination series.\nCambridge Assessment International Education is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of the University of\nCambridge Local Examinations Syndicate (UCLES), which itself is a department of the University of Cambridge.\n© UCLES 2021 9618/33/M/J/21" }, { "id": "9618-2021-mj-41-q01", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 4, "variant": "41", "question_number": 1, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 24, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_41.pdf?download=true", "source_pages": [ 2, 3, 4, 5 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_41.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-mj-41-q01-p01.png", "9618-practical-programming/assets/9618-2021-mj-41-q01-p02.png", "9618-practical-programming/assets/9618-2021-mj-41-q01-p03.png", "9618-practical-programming/assets/9618-2021-mj-41-q01-p04.png" ], "answer": { "status": "available", "id": "9618-2021-mj-41-q01", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_41.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_41.pdf?download=true", "source_pages": [ 4, 5, 6, 7, 8 ], "marks": 24 }, "text_excerpt": "An unordered linked list uses a 1D array to store the data. 1\nEach item in the linked list is of a record type, , with a field and a field .\nnode data nextNode\nThe current contents of the linked list are:\nIndex 0 startPointer data nextNode\n0 1 1\n5 1 5 4 emptyList\n2 6 7\n3 7 -1\n4 2 2\n5 0 6\n6 0 8\n7 56 3\n8 0 9\n9 0 -1\nThe following is pseudocode for the record type . (a)\nnode\nTYPE node\nDECLARE data : INTEGER\nDECLARE nextNode : INTEGER\nENDTYPE\nWrite program code to declare the record type .\nnode\nSave your program as question1.\nCopy and paste the program code into in the evidence document. part 1(a)\n[2]\n© UCLES 2021 9618/41/M/J/21\n3\nWrite program code for the main program. (b)\nDeclare a 1D array of type with the identifier , and initialise it with the data\nnode linkedList\nshown in the table on page 2. Declare the pointers.\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(b)\n[4]\nThe procedure takes the array and as parameters. The (c)\noutputNodes() startPointer\nprocedure outputs the data from the linked list by following the values.\nnextNode\nWrite program code for the procedure . (i)\noutputNodes()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(c)(i)\n[6]\nEdit the main program to call the procedure . (ii)\noutputNodes()\nTake a screenshot to show the output of the procedure .\noutputNodes()\nSave your program.\nCopy and paste the screenshot into in the evidence document. part 1(c)(ii)\n[1]\n[Turn over © UCLES 2021 9618/41/M/J/21\n4\nThe function, , takes the linked list and pointers as parameters, then takes as (d)\naddNode()\ninput the data to be added to the end of the .\nlinkedList\nThe function adds the node in the next available space, updates the pointers and returns\n. If there are no empty nodes, it returns .\nTrue False\nWrite program code for the function . (i)\naddNode()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(d)(i)\n[7]\nEdit the main program to: (ii)\n• call\naddNode()\n• output an appropriate message depending on the result returned from\naddNode()\n• call twice; once before calling and once after calling\noutputNodes() addNode()\n.\naddNode()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(d)(ii)\n[3]\nTest your program by inputting the data value and take a screenshot to show the (iii)\n5\noutput.\nSave your program.\nCopy and paste the screenshot into in the evidence document. part 1(d)(iii)\n[1]\n© UCLES 2021 9618/41/M/J/21\n5\nBLANK PAGE\n[Turn over © UCLES 2021 9618/41/M/J/21" }, { "id": "9618-2021-mj-41-q02", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 4, "variant": "41", "question_number": 2, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 20, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_41.pdf?download=true", "source_pages": [ 6, 7 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_41.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-mj-41-q02-p01.png", "9618-practical-programming/assets/9618-2021-mj-41-q02-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-41-q02", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_41.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_41.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 ], "marks": 20 }, "text_excerpt": "A program stores the following ten integers in a 1D array with the identifier . 2\narrayData\n10 5 6 7 1 12 13 15 21 8\nWrite program code for a to: (a) new program\n• declare the global 1D array, , with ten elements\narrayData\n• initialise in the main program using the data values shown.\narrayData\nSave your program as question2.\nCopy and paste the program code into in the evidence document. part 2(a)\n[2]\nA function, , takes an integer as a parameter and performs a linear (b) (i)\nlinearSearch()\nsearch on to find the parameter value. It returns if it was found and\narrayData True\nif it was not found.\nFalse\nWrite program code for the function .\nlinearSearch()\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(b)(i)\n[6]\nEdit the main program to: (ii)\n• allow the user to input an integer value\n• pass the value to as the parameter\nlinearSearch()\n• output an appropriate message to tell the user whether the search value was found\nor not.\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(b)(ii)\n[4]\nTest your program with one value that is in the array and one value that is not in the (iii)\narray.\nTake a screenshot to show the result of each test.\nSave your program.\nCopy and paste the screenshots into in the evidence document. part 2(b)(iii)\n[2]\n© UCLES 2021 9618/41/M/J/21\n7\nThe following bubble sort pseudocode algorithm sorts the data in into descending (c)\ntheArray\nnumerical order. There are incomplete statements. five\nPROCEDURE bubbleSort()\nDECLARE temp : INTEGER\n0 to ………………………………… FOR x\n0 to ………………………………… FOR y\nIF theArray[y] ………………………………… theArray[y + 1] THEN\ntheArray[y] temp\n………………………………… theArray[y]\n………………………………… theArray[y + 1]\nENDIF\nNEXT y\nNEXT x\nENDPROCEDURE\nWrite program code for the procedure to sort the data in into\nbubbleSort() arrayData\ndescending order.\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(c)\n[6]\n[Turn over © UCLES 2021 9618/41/M/J/21" }, { "id": "9618-2021-mj-41-q03", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 4, "variant": "41", "question_number": 3, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 31, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_41.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_41.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-mj-41-q03-p01.png", "9618-practical-programming/assets/9618-2021-mj-41-q03-p02.png", "9618-practical-programming/assets/9618-2021-mj-41-q03-p03.png", "9618-practical-programming/assets/9618-2021-mj-41-q03-p04.png", "9618-practical-programming/assets/9618-2021-mj-41-q03-p05.png" ], "answer": { "status": "available", "id": "9618-2021-mj-41-q03", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_41.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_41.pdf?download=true", "source_pages": [ 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 ], "marks": 31 }, "text_excerpt": "A computer game requires users to travel around a world to find and open treasure chests. Each 3\ntreasure chest has a mathematics question inside. The user enters the answer. The number of\npoints awarded depends on the number of attempts before the user gives the correct answer.\nThe program will be created using object-oriented programming (OOP).\nThe following class diagram describes the class .\nTreasureChest\nTreasureChest\nquestion : STRING // stores the question\nanswer : INTEGER // stores the answer\npoints : INTEGER // stores the maximum possible number of\npoints available for this chest\nconstructor() // takes question, answer and points as\nparameters and creates an instance of an\nobject\ngetQuestion() // returns the question\ncheckAnswer() // takes the user’s answer as a parameter and\nreturns True if it is correct,\notherwise returns False\ngetPoints() // takes the number of attempts as a\nparameter and returns the number of\npoints awarded\nCreate a new program. (a)\nWrite program code to declare the class .\nTreasureChest\nDo write any other methods. not\nThe attributes are private.\nIf you are using the Python programming language, include attribute declarations using\ncomments.\nSave your program as question3.\nCopy and paste the program code into in the evidence document. part 3(a)\n[5]\n© UCLES 2021 9618/41/M/J/21\n9\nThe text file stores data for five questions, in the order of (b)\nTreasureChestData.txt\nquestion, answer, points.\nFor example, the first three lines of the file are for the first question:\nquestion\n2*2\nanswer\n4\npoints\n10\nWrite program code for the procedure, to:\nreadData()\n• read each question, answer and points from the text file\n• create an object of type for each question\nTreasureChest\n• declare an array named of type\narrayTreasure TreasureChest\n• append each object to the array\n• use exception handling to output an appropriate message if the file is not found.\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(b)\n[8]\n[Turn over © UCLES 2021 9618/41/M/J/21\n10\nThe main program repeats each question until the user inputs the correct answer. The (c)\nnumber of points awarded depends on the number of attempts before the user gives the\ncorrect answer.\nThe class has a method that returns the question. (i)\nTreasureChest getQuestion()\nWrite the method .\ngetQuestion()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(c)(i)\n[1]\nThe class has a method that takes the user’s (ii)\nTreasureChest checkAnswer()\nanswer as a parameter. It returns if the answer is correct and otherwise.\nTrue False\nWrite the method .\ncheckAnswer()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(c)(ii)\n[3]\nThe class has a method that takes the number of (iii)\nTreasureChest getPoints()\nattempts as a parameter.\n• If the number of attempts is 1, it returns the value of .\npoints\n• If the number of attempts is 2, it returns the integer value of divided by\npoints\n2 ( )." }, { "id": "9618-2021-mj-42-q01", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 4, "variant": "42", "question_number": 1, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 24, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_42.pdf?download=true", "source_pages": [ 2, 3, 4, 5 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_42.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-mj-42-q01-p01.png", "9618-practical-programming/assets/9618-2021-mj-42-q01-p02.png", "9618-practical-programming/assets/9618-2021-mj-42-q01-p03.png", "9618-practical-programming/assets/9618-2021-mj-42-q01-p04.png" ], "answer": { "status": "available", "id": "9618-2021-mj-42-q01", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_42.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_42.pdf?download=true", "source_pages": [ 4, 5, 6, 7, 8 ], "marks": 24 }, "text_excerpt": "An unordered linked list uses a 1D array to store the data. 1\nEach item in the linked list is of a record type, , with a field and a field .\nnode data nextNode\nThe current contents of the linked list are:\nIndex 0 startPointer data nextNode\n0 1 1\n5 1 5 4 emptyList\n2 6 7\n3 7 -1\n4 2 2\n5 0 6\n6 0 8\n7 56 3\n8 0 9\n9 0 -1\nThe following is pseudocode for the record type . (a)\nnode\nTYPE node\nDECLARE data : INTEGER\nDECLARE nextNode : INTEGER\nENDTYPE\nWrite program code to declare the record type .\nnode\nSave your program as question1.\nCopy and paste the program code into in the evidence document. part 1(a)\n[2]\n© UCLES 2021 9618/42/M/J/21\n3\nWrite program code for the main program. (b)\nDeclare a 1D array of type with the identifier , and initialise it with the data\nnode linkedList\nshown in the table on page 2. Declare the pointers.\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(b)\n[4]\nThe procedure takes the array and as parameters. The (c)\noutputNodes() startPointer\nprocedure outputs the data from the linked list by following the values.\nnextNode\nWrite program code for the procedure . (i)\noutputNodes()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(c)(i)\n[6]\nEdit the main program to call the procedure . (ii)\noutputNodes()\nTake a screenshot to show the output of the procedure .\noutputNodes()\nSave your program.\nCopy and paste the screenshot into in the evidence document. part 1(c)(ii)\n[1]\n[Turn over © UCLES 2021 9618/42/M/J/21\n4\nThe function, , takes the linked list and pointers as parameters, then takes as (d)\naddNode()\ninput the data to be added to the end of the .\nlinkedList\nThe function adds the node in the next available space, updates the pointers and returns\n. If there are no empty nodes, it returns .\nTrue False\nWrite program code for the function . (i)\naddNode()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(d)(i)\n[7]\nEdit the main program to: (ii)\n• call\naddNode()\n• output an appropriate message depending on the result returned from\naddNode()\n• call twice; once before calling and once after calling\noutputNodes() addNode()\n.\naddNode()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(d)(ii)\n[3]\nTest your program by inputting the data value and take a screenshot to show the (iii)\n5\noutput.\nSave your program.\nCopy and paste the screenshot into in the evidence document. part 1(d)(iii)\n[1]\n© UCLES 2021 9618/42/M/J/21\n5\nBLANK PAGE\n[Turn over © UCLES 2021 9618/42/M/J/21" }, { "id": "9618-2021-mj-42-q02", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 4, "variant": "42", "question_number": 2, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 20, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_42.pdf?download=true", "source_pages": [ 6, 7 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_42.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-mj-42-q02-p01.png", "9618-practical-programming/assets/9618-2021-mj-42-q02-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-42-q02", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_42.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_42.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 ], "marks": 20 }, "text_excerpt": "A program stores the following ten integers in a 1D array with the identifier . 2\narrayData\n10 5 6 7 1 12 13 15 21 8\nWrite program code for a to: (a) new program\n• declare the global 1D array, , with ten elements\narrayData\n• initialise in the main program using the data values shown.\narrayData\nSave your program as question2.\nCopy and paste the program code into in the evidence document. part 2(a)\n[2]\nA function, , takes an integer as a parameter and performs a linear (b) (i)\nlinearSearch()\nsearch on to find the parameter value. It returns if it was found and\narrayData True\nif it was not found.\nFalse\nWrite program code for the function .\nlinearSearch()\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(b)(i)\n[6]\nEdit the main program to: (ii)\n• allow the user to input an integer value\n• pass the value to as the parameter\nlinearSearch()\n• output an appropriate message to tell the user whether the search value was found\nor not.\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(b)(ii)\n[4]\nTest your program with one value that is in the array and one value that is not in the (iii)\narray.\nTake a screenshot to show the result of each test.\nSave your program.\nCopy and paste the screenshots into in the evidence document. part 2(b)(iii)\n[2]\n© UCLES 2021 9618/42/M/J/21\n7\nThe following bubble sort pseudocode algorithm sorts the data in into descending (c)\ntheArray\nnumerical order. There are incomplete statements. five\nPROCEDURE bubbleSort()\nDECLARE temp : INTEGER\n0 to ………………………………… FOR x\n0 to ………………………………… FOR y\nIF theArray[y] ………………………………… theArray[y + 1] THEN\ntheArray[y] temp\n………………………………… theArray[y]\n………………………………… theArray[y + 1]\nENDIF\nNEXT y\nNEXT x\nENDPROCEDURE\nWrite program code for the procedure to sort the data in into\nbubbleSort() arrayData\ndescending order.\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(c)\n[6]\n[Turn over © UCLES 2021 9618/42/M/J/21" }, { "id": "9618-2021-mj-42-q03", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 4, "variant": "42", "question_number": 3, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 31, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_42.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_42.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-mj-42-q03-p01.png", "9618-practical-programming/assets/9618-2021-mj-42-q03-p02.png", "9618-practical-programming/assets/9618-2021-mj-42-q03-p03.png", "9618-practical-programming/assets/9618-2021-mj-42-q03-p04.png", "9618-practical-programming/assets/9618-2021-mj-42-q03-p05.png" ], "answer": { "status": "available", "id": "9618-2021-mj-42-q03", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_42.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_42.pdf?download=true", "source_pages": [ 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 ], "marks": 31 }, "text_excerpt": "A computer game requires users to travel around a world to find and open treasure chests. Each 3\ntreasure chest has a mathematics question inside. The user enters the answer. The number of\npoints awarded depends on the number of attempts before the user gives the correct answer.\nThe program will be created using object-oriented programming (OOP).\nThe following class diagram describes the class .\nTreasureChest\nTreasureChest\nquestion : STRING // stores the question\nanswer : INTEGER // stores the answer\npoints : INTEGER // stores the maximum possible number of\npoints available for this chest\nconstructor() // takes question, answer and points as\nparameters and creates an instance of an\nobject\ngetQuestion() // returns the question\ncheckAnswer() // takes the user’s answer as a parameter and\nreturns True if it is correct,\notherwise returns False\ngetPoints() // takes the number of attempts as a\nparameter and returns the number of\npoints awarded\nCreate a new program. (a)\nWrite program code to declare the class .\nTreasureChest\nDo write any other methods. not\nThe attributes are private.\nIf you are using the Python programming language, include attribute declarations using\ncomments.\nSave your program as question3.\nCopy and paste the program code into in the evidence document. part 3(a)\n[5]\n© UCLES 2021 9618/42/M/J/21\n9\nThe text file stores data for five questions, in the order of (b)\nTreasureChestData.txt\nquestion, answer, points.\nFor example, the first three lines of the file are for the first question:\nquestion\n2*2\nanswer\n4\npoints\n10\nWrite program code for the procedure, to:\nreadData()\n• read each question, answer and points from the text file\n• create an object of type for each question\nTreasureChest\n• declare an array named of type\narrayTreasure TreasureChest\n• append each object to the array\n• use exception handling to output an appropriate message if the file is not found.\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(b)\n[8]\n[Turn over © UCLES 2021 9618/42/M/J/21\n10\nThe main program repeats each question until the user inputs the correct answer. The (c)\nnumber of points awarded depends on the number of attempts before the user gives the\ncorrect answer.\nThe class has a method that returns the question. (i)\nTreasureChest getQuestion()\nWrite the method .\ngetQuestion()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(c)(i)\n[1]\nThe class has a method that takes the user’s (ii)\nTreasureChest checkAnswer()\nanswer as a parameter. It returns if the answer is correct and otherwise.\nTrue False\nWrite the method .\ncheckAnswer()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(c)(ii)\n[3]\nThe class has a method that takes the number of (iii)\nTreasureChest getPoints()\nattempts as a parameter.\n• If the number of attempts is 1, it returns the value of .\npoints\n• If the number of attempts is 2, it returns the integer value of divided by\npoints\n2 ( )." }, { "id": "9618-2021-mj-43-q01", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 4, "variant": "43", "question_number": 1, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 24, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_43.pdf?download=true", "source_pages": [ 2, 3, 4, 5 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_43.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-mj-43-q01-p01.png", "9618-practical-programming/assets/9618-2021-mj-43-q01-p02.png", "9618-practical-programming/assets/9618-2021-mj-43-q01-p03.png", "9618-practical-programming/assets/9618-2021-mj-43-q01-p04.png" ], "answer": { "status": "available", "id": "9618-2021-mj-43-q01", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_43.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_43.pdf?download=true", "source_pages": [ 4, 5, 6, 7, 8 ], "marks": 24 }, "text_excerpt": "An unordered linked list uses a 1D array to store the data. 1\nEach item in the linked list is of a record type, , with a field and a field .\nnode data nextNode\nThe current contents of the linked list are:\nIndex 0 startPointer data nextNode\n0 1 1\n5 1 5 4 emptyList\n2 6 7\n3 7 -1\n4 2 2\n5 0 6\n6 0 8\n7 56 3\n8 0 9\n9 0 -1\nThe following is pseudocode for the record type . (a)\nnode\nTYPE node\nDECLARE data : INTEGER\nDECLARE nextNode : INTEGER\nENDTYPE\nWrite program code to declare the record type .\nnode\nSave your program as question1.\nCopy and paste the program code into in the evidence document. part 1(a)\n[2]\n© UCLES 2021 9618/43/M/J/21\n3\nWrite program code for the main program. (b)\nDeclare a 1D array of type with the identifier , and initialise it with the data\nnode linkedList\nshown in the table on page 2. Declare the pointers.\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(b)\n[4]\nThe procedure takes the array and as parameters. The (c)\noutputNodes() startPointer\nprocedure outputs the data from the linked list by following the values.\nnextNode\nWrite program code for the procedure . (i)\noutputNodes()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(c)(i)\n[6]\nEdit the main program to call the procedure . (ii)\noutputNodes()\nTake a screenshot to show the output of the procedure .\noutputNodes()\nSave your program.\nCopy and paste the screenshot into in the evidence document. part 1(c)(ii)\n[1]\n[Turn over © UCLES 2021 9618/43/M/J/21\n4\nThe function, , takes the linked list and pointers as parameters, then takes as (d)\naddNode()\ninput the data to be added to the end of the .\nlinkedList\nThe function adds the node in the next available space, updates the pointers and returns\n. If there are no empty nodes, it returns .\nTrue False\nWrite program code for the function . (i)\naddNode()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(d)(i)\n[7]\nEdit the main program to: (ii)\n• call\naddNode()\n• output an appropriate message depending on the result returned from\naddNode()\n• call twice; once before calling and once after calling\noutputNodes() addNode()\n.\naddNode()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(d)(ii)\n[3]\nTest your program by inputting the data value and take a screenshot to show the (iii)\n5\noutput.\nSave your program.\nCopy and paste the screenshot into in the evidence document. part 1(d)(iii)\n[1]\n© UCLES 2021 9618/43/M/J/21\n5\nBLANK PAGE\n[Turn over © UCLES 2021 9618/43/M/J/21" }, { "id": "9618-2021-mj-43-q02", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 4, "variant": "43", "question_number": 2, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 20, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_43.pdf?download=true", "source_pages": [ 6, 7 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_43.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-mj-43-q02-p01.png", "9618-practical-programming/assets/9618-2021-mj-43-q02-p02.png" ], "answer": { "status": "available", "id": "9618-2021-mj-43-q02", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_43.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_43.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 ], "marks": 20 }, "text_excerpt": "A program stores the following ten integers in a 1D array with the identifier . 2\narrayData\n10 5 6 7 1 12 13 15 21 8\nWrite program code for a to: (a) new program\n• declare the global 1D array, , with ten elements\narrayData\n• initialise in the main program using the data values shown.\narrayData\nSave your program as question2.\nCopy and paste the program code into in the evidence document. part 2(a)\n[2]\nA function, , takes an integer as a parameter and performs a linear (b) (i)\nlinearSearch()\nsearch on to find the parameter value. It returns if it was found and\narrayData True\nif it was not found.\nFalse\nWrite program code for the function .\nlinearSearch()\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(b)(i)\n[6]\nEdit the main program to: (ii)\n• allow the user to input an integer value\n• pass the value to as the parameter\nlinearSearch()\n• output an appropriate message to tell the user whether the search value was found\nor not.\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(b)(ii)\n[4]\nTest your program with one value that is in the array and one value that is not in the (iii)\narray.\nTake a screenshot to show the result of each test.\nSave your program.\nCopy and paste the screenshots into in the evidence document. part 2(b)(iii)\n[2]\n© UCLES 2021 9618/43/M/J/21\n7\nThe following bubble sort pseudocode algorithm sorts the data in into descending (c)\ntheArray\nnumerical order. There are incomplete statements. five\nPROCEDURE bubbleSort()\nDECLARE temp : INTEGER\n0 to ………………………………… FOR x\n0 to ………………………………… FOR y\nIF theArray[y] ………………………………… theArray[y + 1] THEN\ntheArray[y] temp\n………………………………… theArray[y]\n………………………………… theArray[y + 1]\nENDIF\nNEXT y\nNEXT x\nENDPROCEDURE\nWrite program code for the procedure to sort the data in into\nbubbleSort() arrayData\ndescending order.\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(c)\n[6]\n[Turn over © UCLES 2021 9618/43/M/J/21" }, { "id": "9618-2021-mj-43-q03", "subject": "9618", "year": 2021, "session": "May/June", "session_code": "mj", "paper": 4, "variant": "43", "question_number": 3, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 31, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_qp_43.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12 ], "local_pdf": "_source-pdfs/2021-may-june/qp/9618_s21_qp_43.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-mj-43-q03-p01.png", "9618-practical-programming/assets/9618-2021-mj-43-q03-p02.png", "9618-practical-programming/assets/9618-2021-mj-43-q03-p03.png", "9618-practical-programming/assets/9618-2021-mj-43-q03-p04.png", "9618-practical-programming/assets/9618-2021-mj-43-q03-p05.png" ], "answer": { "status": "available", "id": "9618-2021-mj-43-q03", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-may-june/ms/9618_s21_ms_43.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-May-June/9618_s21_ms_43.pdf?download=true", "source_pages": [ 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 ], "marks": 31 }, "text_excerpt": "A computer game requires users to travel around a world to find and open treasure chests. Each 3\ntreasure chest has a mathematics question inside. The user enters the answer. The number of\npoints awarded depends on the number of attempts before the user gives the correct answer.\nThe program will be created using object-oriented programming (OOP).\nThe following class diagram describes the class .\nTreasureChest\nTreasureChest\nquestion : STRING // stores the question\nanswer : INTEGER // stores the answer\npoints : INTEGER // stores the maximum possible number of\npoints available for this chest\nconstructor() // takes question, answer and points as\nparameters and creates an instance of an\nobject\ngetQuestion() // returns the question\ncheckAnswer() // takes the user’s answer as a parameter and\nreturns True if it is correct,\notherwise returns False\ngetPoints() // takes the number of attempts as a\nparameter and returns the number of\npoints awarded\nCreate a new program. (a)\nWrite program code to declare the class .\nTreasureChest\nDo write any other methods. not\nThe attributes are private.\nIf you are using the Python programming language, include attribute declarations using\ncomments.\nSave your program as question3.\nCopy and paste the program code into in the evidence document. part 3(a)\n[5]\n© UCLES 2021 9618/43/M/J/21\n9\nThe text file stores data for five questions, in the order of (b)\nTreasureChestData.txt\nquestion, answer, points.\nFor example, the first three lines of the file are for the first question:\nquestion\n2*2\nanswer\n4\npoints\n10\nWrite program code for the procedure, to:\nreadData()\n• read each question, answer and points from the text file\n• create an object of type for each question\nTreasureChest\n• declare an array named of type\narrayTreasure TreasureChest\n• append each object to the array\n• use exception handling to output an appropriate message if the file is not found.\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(b)\n[8]\n[Turn over © UCLES 2021 9618/43/M/J/21\n10\nThe main program repeats each question until the user inputs the correct answer. The (c)\nnumber of points awarded depends on the number of attempts before the user gives the\ncorrect answer.\nThe class has a method that returns the question. (i)\nTreasureChest getQuestion()\nWrite the method .\ngetQuestion()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(c)(i)\n[1]\nThe class has a method that takes the user’s (ii)\nTreasureChest checkAnswer()\nanswer as a parameter. It returns if the answer is correct and otherwise.\nTrue False\nWrite the method .\ncheckAnswer()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(c)(ii)\n[3]\nThe class has a method that takes the number of (iii)\nTreasureChest getPoints()\nattempts as a parameter.\n• If the number of attempts is 1, it returns the value of .\npoints\n• If the number of attempts is 2, it returns the integer value of divided by\npoints\n2 ( )." }, { "id": "9618-2021-on-31-q01", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 1, "topic_number": 13, "topic": "Data representation", "topic_slug": "9618-topic-13-data-representation", "marks": 7, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 2 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-13-data-representation/assets/9618-2021-on-31-q01-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q01", "html": "9618-topic-13-data-representation/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 3 ], "marks": 7 }, "text_excerpt": "Numbers are stored in a computer using floating-point representation with: 1 (a)\n• 12 bits for the mantissa\n• 4 bits for the exponent\n• two’s complement form for both the mantissa and exponent.\nWrite the normalised floating-point representation of the following unsigned binary (i)\nnumber using this system.\n1011100.011001\nWorking .............................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\nMantissa Exponent\n[2]\nState the consequence of storing the binary number in as a floating-point (ii) part (a)(i)\nnumber in this system. Justify your answer.\nConsequence ....................................................................................................................\n...........................................................................................................................................\nJustification .......................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n[2]\nExplain the reason why binary numbers are stored in normalised form. (b)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [3]\n© UCLES 2021 9618/31/O/N/21" }, { "id": "9618-2021-on-31-q02", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 2, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 4, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 3 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-on-31-q02-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q02", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 4 ], "marks": 4 }, "text_excerpt": "Draw line from each programming paradigm to its description. 2 one most appropriate\nProgramming paradigm Description\nPrograms using the instruction set of a\nprocessor\nDeclarative\nPrograms based on events such as user\nactions or sensor outputs\nImperative\nPrograms using the concepts of class,\ninheritance, encapsulation and\npolymorphism\nLow-level\nPrograms with an explicit sequence of\ncommands that update the program state,\nwith or without procedure calls Object-oriented\nPrograms that specify the desired result\nrather than how to get to it\n[4]" }, { "id": "9618-2021-on-31-q03", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 3, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 4, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 3 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-on-31-q03-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q03", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 4 ], "marks": 4 }, "text_excerpt": "Enumerated and pointer are two non-composite data types. 3\nWrite to create an enumerated type called to include these parts sold in (a) pseudocode\nParts\na computer shop:\nMonitor, CPU, SSD, HDD, LaserPrinter, Keyboard, Mouse\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nWrite to create a pointer type called that will reference the (b) pseudocode\nSelectParts\nmemory location in which the current part name is stored.\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\n[Turn over © UCLES 2021 9618/31/O/N/21" }, { "id": "9618-2021-on-31-q04", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 4, "topic_number": 16, "topic": "System software", "topic_slug": "9618-topic-16-system-software", "marks": 7, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 4, 5 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-16-system-software/assets/9618-2021-on-31-q04-p01.png", "9618-topic-16-system-software/assets/9618-2021-on-31-q04-p02.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q04", "html": "9618-topic-16-system-software/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 5 ], "marks": 7 }, "text_excerpt": "The following syntax diagrams for a particular programming language show the syntax of: 4\n• a digit\n• a capital letter\n• a character.\ndigit capital letter\n0 A\n1 E\n2 I\n3 O\n4 U\n5 character\n$\n6\n%\n7\n&\n8\n*\n9\n#\nWrite the Backus-Naur Form (BNF) notation of the syntax diagram for character. (a)\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\n© UCLES 2021 9618/31/O/N/21\n5\nA password must begin with a character and be followed by one or more digits or capital (b)\nletters.\nState an example of a valid password. (i)\n..................................................................................................................................... [1]\nA valid password is represented by the syntax diagram: (ii)\npassword\ncharacter digit\ncapital letter\nWrite the BNF notation of the syntax diagram for password.\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [4]\n[Turn over © UCLES 2021 9618/31/O/N/21" }, { "id": "9618-2021-on-31-q05", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 5, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 6, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 6 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2021-on-31-q05-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q05", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 5 ], "marks": 6 }, "text_excerpt": "Compare sequential and serial methods of file organisation. 5 (a)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [4]\nState the most suitable method of file access when a record is referenced by a unique (b)\naddress on a disk-type storage medium.\n............................................................................................................................................. [1]\nState the most suitable method of file access when a bank stores its data records in ascending (c)\norder of account number.\n............................................................................................................................................. [1]\n© UCLES 2021 9618/31/O/N/21" }, { "id": "9618-2021-on-31-q06", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 6, "topic_number": 14, "topic": "Communication and internet technologies", "topic_slug": "9618-topic-14-communication-and-internet-technologies", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 7 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-14-communication-and-internet-technologies/assets/9618-2021-on-31-q06-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q06", "html": "9618-topic-14-communication-and-internet-technologies/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 6 ], "marks": 8 }, "text_excerpt": "Explain how packet switching is used to transfer messages across the internet. 6 (a)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [5]\nOutline the function of a router in packet switching. (b)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [3]\n[Turn over © UCLES 2021 9618/31/O/N/21" }, { "id": "9618-2021-on-31-q07", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 7, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 10, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 8, 9 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-on-31-q07-p01.png", "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-on-31-q07-p02.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q07", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 7 ], "marks": 10 }, "text_excerpt": "Write the Boolean expression that corresponds to the given truth table as a sum-of-products. 7 (a)\nINPUT OUTPUT\nA B C D Z\n0 0 0 0 0\n0 0 0 1 0\n0 0 1 0 0\n0 0 1 1 0\n0 1 0 0 0\n0 1 0 1 0\n0 1 1 0 0\n0 1 1 1 0\n1 0 0 0 0\n1 0 0 1 1\n1 0 1 0 0\n1 0 1 1 1\n1 1 0 0 1\n1 1 0 1 1\n1 1 1 0 1\n1 1 1 1 1\n= ............................................................................................................................................ Z\n............................................................................................................................................. [3]\n© UCLES 2021 9618/31/O/N/21\n9\nComplete the Karnaugh map (K-map) for the given truth table. (b) (i)\nAB\n00 01 11 10 CD\n00\n01\n11\n10\n[2]\nDraw loop(s) around appropriate group(s) of 1s in the K-map to produce an optimal (ii)\nsum-of-products. [2]\nWrite the Boolean expression from your answer to as a simplified (iii) part b(ii)\nsum-of-products.\n= ..................................................................................................................................... Z\n..................................................................................................................................... [2]\nWrite the simplified Boolean expression for your answer to b(iii). (iv) part\n= ..................................................................................................................................... Z\n..................................................................................................................................... [1]\n[Turn over © UCLES 2021 9618/31/O/N/21" }, { "id": "9618-2021-on-31-q08", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 8, "topic_number": 17, "topic": "Security", "topic_slug": "9618-topic-17-security", "marks": 6, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 10 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-17-security/assets/9618-2021-on-31-q08-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q08", "html": "9618-topic-17-security/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 8 ], "marks": 6 }, "text_excerpt": "Describe the purpose of the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) 8 (a)\nprotocols.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nExplain how SSL/TLS protocols are used when a client-server communication is initiated. (b)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [4]\n© UCLES 2021 9618/31/O/N/21" }, { "id": "9618-2021-on-31-q09", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 9, "topic_number": 18, "topic": "Artificial intelligence (AI)", "topic_slug": "9618-topic-18-artificial-intelligence", "marks": 10, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 11, 12 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-18-artificial-intelligence/assets/9618-2021-on-31-q09-p01.png", "9618-topic-18-artificial-intelligence/assets/9618-2021-on-31-q09-p02.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q09", "html": "9618-topic-18-artificial-intelligence/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 8, 9 ], "marks": 10 }, "text_excerpt": "The diagram shown represents an artificial neural network. 9 (a)\nOutput\nLayer\nInput\nLayer\nHidden Hidden\nHidden Layer 1 Layer 3\nLayer 2\nState the reason for having multiple hidden layers in an artificial neural network. (i)\n...........................................................................................................................................\n..................................................................................................................................... [1]\nExplain how artificial neural networks enable machine learning. (ii)\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [4]\n[Turn over © UCLES 2021 9618/31/O/N/21\n12\nFind the shortest path between the Home and School nodes using the A* algorithm. (b)\nShow your working in the table provided.\nThe first two rows in the table have been completed.\n14\nHome\n9 h = 10 4 g = 1\n5 A C\n3\n7\nB 6\n2\n6\nD 6\n3\n7\nF\n1\n2\n3\nE\n3 5\nSchool\nNode Cost from Home node (g) Heuristic (h) Total (f = g + h)\nHome 0 14 14\nA 1 10 11\nFinal path\n[5]\n© UCLES 2021 9618/31/O/N/21" }, { "id": "9618-2021-on-31-q10", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "31", "question_number": 10, "topic_number": 19, "topic": "Computational thinking and problem-solving", "topic_slug": "9618-topic-19-computational-thinking-and-problem-solving", "marks": 13, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_31.pdf?download=true", "source_pages": [ 13, 14, 15, 16 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_31.pdf", "image_paths": [ "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-on-31-q10-p01.png", "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-on-31-q10-p02.png", "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-on-31-q10-p03.png", "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-on-31-q10-p04.png" ], "answer": { "status": "available", "id": "9618-2021-on-31-q10", "html": "9618-topic-19-computational-thinking-and-problem-solving/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_31.pdf?download=true", "source_pages": [ 10 ], "marks": 13 }, "text_excerpt": "State essential features of recursion. 10 (a) three\n1 ................................................................................................................................................\n...................................................................................................................................................\n2 ................................................................................................................................................\n...................................................................................................................................................\n3 ................................................................................................................................................\n...................................................................................................................................................\n[3]\nExplain the reasons why a stack is a suitable Abstract Data Type (ADT) to implement (b)\nrecursion.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [3]\nIdentify ADTs other than a stack. (c) two\n1 ................................................................................................................................................\n2 ................................................................................................................................................\n[2]\n[Turn over © UCLES 2021 9618/31/O/N/21\n14\nThe function checks whether a stack is full. (d)\nStackFull()\nThe function uses the variable to represent the pointer to the most recent\nTopOfStack\nposition used on the stack, and the variable to represent the maximum size of the stack.\nMax\nAssume and are global variables.\nTopOfStack Max\nFUNCTION StackFull() RETURNS BOOLEAN\nIF TopOfStack = Max THEN\nRETURN TRUE\nELSE\nRETURN FALSE\nENDIF\nENDFUNCTION\nAn algorithm is required to add a new integer data element to a stack.\nAddInteger\nThe stack is implemented as an array .\nArrayStack\nThe function calls and returns an appropriate message.\nAddInteger() StackFull()\nComplete the pseudocode for the function .\nAddInteger()\nFUNCTION AddInteger(NewInt" }, { "id": "9618-2021-on-32-q01", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 1, "topic_number": 13, "topic": "Data representation", "topic_slug": "9618-topic-13-data-representation", "marks": 7, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 2 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-13-data-representation/assets/9618-2021-on-32-q01-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q01", "html": "9618-topic-13-data-representation/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 3 ], "marks": 7 }, "text_excerpt": "Numbers are stored in a computer using floating-point representation with: 1 (a)\n• 12 bits for the mantissa\n• 4 bits for the exponent\n• two’s complement form for both the mantissa and exponent.\nWrite the normalised floating-point representation of the following unsigned binary (i)\nnumber using this system.\n1011100.011001\nWorking .............................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\nMantissa Exponent\n[2]\nState the consequence of storing the binary number in as a floating-point (ii) part (a)(i)\nnumber in this system. Justify your answer.\nConsequence ....................................................................................................................\n...........................................................................................................................................\nJustification .......................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n[2]\nExplain the reason why binary numbers are stored in normalised form. (b)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [3]\n© UCLES 2021 9618/32/O/N/21" }, { "id": "9618-2021-on-32-q02", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 2, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 4, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 3 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-on-32-q02-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q02", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 4 ], "marks": 4 }, "text_excerpt": "Draw line from each programming paradigm to its description. 2 one most appropriate\nProgramming paradigm Description\nPrograms using the instruction set of a\nprocessor\nDeclarative\nPrograms based on events such as user\nactions or sensor outputs\nImperative\nPrograms using the concepts of class,\ninheritance, encapsulation and\npolymorphism\nLow-level\nPrograms with an explicit sequence of\ncommands that update the program state,\nwith or without procedure calls Object-oriented\nPrograms that specify the desired result\nrather than how to get to it\n[4]" }, { "id": "9618-2021-on-32-q03", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 3, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 4, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 3 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-on-32-q03-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q03", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 4 ], "marks": 4 }, "text_excerpt": "Enumerated and pointer are two non-composite data types. 3\nWrite to create an enumerated type called to include these parts sold in (a) pseudocode\nParts\na computer shop:\nMonitor, CPU, SSD, HDD, LaserPrinter, Keyboard, Mouse\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nWrite to create a pointer type called that will reference the (b) pseudocode\nSelectParts\nmemory location in which the current part name is stored.\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\n[Turn over © UCLES 2021 9618/32/O/N/21" }, { "id": "9618-2021-on-32-q04", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 4, "topic_number": 16, "topic": "System software", "topic_slug": "9618-topic-16-system-software", "marks": 7, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 4, 5 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-16-system-software/assets/9618-2021-on-32-q04-p01.png", "9618-topic-16-system-software/assets/9618-2021-on-32-q04-p02.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q04", "html": "9618-topic-16-system-software/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 5 ], "marks": 7 }, "text_excerpt": "The following syntax diagrams for a particular programming language show the syntax of: 4\n• a digit\n• a capital letter\n• a character.\ndigit capital letter\n0 A\n1 E\n2 I\n3 O\n4 U\n5 character\n$\n6\n%\n7\n&\n8\n*\n9\n#\nWrite the Backus-Naur Form (BNF) notation of the syntax diagram for character. (a)\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\n© UCLES 2021 9618/32/O/N/21\n5\nA password must begin with a character and be followed by one or more digits or capital (b)\nletters.\nState an example of a valid password. (i)\n..................................................................................................................................... [1]\nA valid password is represented by the syntax diagram: (ii)\npassword\ncharacter digit\ncapital letter\nWrite the BNF notation of the syntax diagram for password.\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [4]\n[Turn over © UCLES 2021 9618/32/O/N/21" }, { "id": "9618-2021-on-32-q05", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 5, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 6, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 6 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2021-on-32-q05-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q05", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 5 ], "marks": 6 }, "text_excerpt": "Compare sequential and serial methods of file organisation. 5 (a)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [4]\nState the most suitable method of file access when a record is referenced by a unique (b)\naddress on a disk-type storage medium.\n............................................................................................................................................. [1]\nState the most suitable method of file access when a bank stores its data records in ascending (c)\norder of account number.\n............................................................................................................................................. [1]\n© UCLES 2021 9618/32/O/N/21" }, { "id": "9618-2021-on-32-q06", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 6, "topic_number": 14, "topic": "Communication and internet technologies", "topic_slug": "9618-topic-14-communication-and-internet-technologies", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 7 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-14-communication-and-internet-technologies/assets/9618-2021-on-32-q06-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q06", "html": "9618-topic-14-communication-and-internet-technologies/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 6 ], "marks": 8 }, "text_excerpt": "Explain how packet switching is used to transfer messages across the internet. 6 (a)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [5]\nOutline the function of a router in packet switching. (b)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [3]\n[Turn over © UCLES 2021 9618/32/O/N/21" }, { "id": "9618-2021-on-32-q07", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 7, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 10, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 8, 9 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-on-32-q07-p01.png", "9618-topic-15-hardware-and-virtual-machines/assets/9618-2021-on-32-q07-p02.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q07", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 7 ], "marks": 10 }, "text_excerpt": "Write the Boolean expression that corresponds to the given truth table as a sum-of-products. 7 (a)\nINPUT OUTPUT\nA B C D Z\n0 0 0 0 0\n0 0 0 1 0\n0 0 1 0 0\n0 0 1 1 0\n0 1 0 0 0\n0 1 0 1 0\n0 1 1 0 0\n0 1 1 1 0\n1 0 0 0 0\n1 0 0 1 1\n1 0 1 0 0\n1 0 1 1 1\n1 1 0 0 1\n1 1 0 1 1\n1 1 1 0 1\n1 1 1 1 1\n= ............................................................................................................................................ Z\n............................................................................................................................................. [3]\n© UCLES 2021 9618/32/O/N/21\n9\nComplete the Karnaugh map (K-map) for the given truth table. (b) (i)\nAB\n00 01 11 10 CD\n00\n01\n11\n10\n[2]\nDraw loop(s) around appropriate group(s) of 1s in the K-map to produce an optimal (ii)\nsum-of-products. [2]\nWrite the Boolean expression from your answer to as a simplified (iii) part b(ii)\nsum-of-products.\n= ..................................................................................................................................... Z\n..................................................................................................................................... [2]\nWrite the simplified Boolean expression for your answer to b(iii). (iv) part\n= ..................................................................................................................................... Z\n..................................................................................................................................... [1]\n[Turn over © UCLES 2021 9618/32/O/N/21" }, { "id": "9618-2021-on-32-q08", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 8, "topic_number": 17, "topic": "Security", "topic_slug": "9618-topic-17-security", "marks": 6, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 10 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-17-security/assets/9618-2021-on-32-q08-p01.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q08", "html": "9618-topic-17-security/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 8 ], "marks": 6 }, "text_excerpt": "Describe the purpose of the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) 8 (a)\nprotocols.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nExplain how SSL/TLS protocols are used when a client-server communication is initiated. (b)\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [4]\n© UCLES 2021 9618/32/O/N/21" }, { "id": "9618-2021-on-32-q09", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 9, "topic_number": 18, "topic": "Artificial intelligence (AI)", "topic_slug": "9618-topic-18-artificial-intelligence", "marks": 10, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 11, 12 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-18-artificial-intelligence/assets/9618-2021-on-32-q09-p01.png", "9618-topic-18-artificial-intelligence/assets/9618-2021-on-32-q09-p02.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q09", "html": "9618-topic-18-artificial-intelligence/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 8, 9 ], "marks": 10 }, "text_excerpt": "The diagram shown represents an artificial neural network. 9 (a)\nOutput\nLayer\nInput\nLayer\nHidden Hidden\nHidden Layer 1 Layer 3\nLayer 2\nState the reason for having multiple hidden layers in an artificial neural network. (i)\n...........................................................................................................................................\n..................................................................................................................................... [1]\nExplain how artificial neural networks enable machine learning. (ii)\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [4]\n[Turn over © UCLES 2021 9618/32/O/N/21\n12\nFind the shortest path between the Home and School nodes using the A* algorithm. (b)\nShow your working in the table provided.\nThe first two rows in the table have been completed.\n14\nHome\n9 h = 10 4 g = 1\n5 A C\n3\n7\nB 6\n2\n6\nD 6\n3\n7\nF\n1\n2\n3\nE\n3 5\nSchool\nNode Cost from Home node (g) Heuristic (h) Total (f = g + h)\nHome 0 14 14\nA 1 10 11\nFinal path\n[5]\n© UCLES 2021 9618/32/O/N/21" }, { "id": "9618-2021-on-32-q10", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 3, "variant": "32", "question_number": 10, "topic_number": 19, "topic": "Computational thinking and problem-solving", "topic_slug": "9618-topic-19-computational-thinking-and-problem-solving", "marks": 13, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_32.pdf?download=true", "source_pages": [ 13, 14, 15, 16 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_32.pdf", "image_paths": [ "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-on-32-q10-p01.png", "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-on-32-q10-p02.png", "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-on-32-q10-p03.png", "9618-topic-19-computational-thinking-and-problem-solving/assets/9618-2021-on-32-q10-p04.png" ], "answer": { "status": "available", "id": "9618-2021-on-32-q10", "html": "9618-topic-19-computational-thinking-and-problem-solving/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_32.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_32.pdf?download=true", "source_pages": [ 10 ], "marks": 13 }, "text_excerpt": "State essential features of recursion. 10 (a) three\n1 ................................................................................................................................................\n...................................................................................................................................................\n2 ................................................................................................................................................\n...................................................................................................................................................\n3 ................................................................................................................................................\n...................................................................................................................................................\n[3]\nExplain the reasons why a stack is a suitable Abstract Data Type (ADT) to implement (b)\nrecursion.\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [3]\nIdentify ADTs other than a stack. (c) two\n1 ................................................................................................................................................\n2 ................................................................................................................................................\n[2]\n[Turn over © UCLES 2021 9618/32/O/N/21\n14\nThe function checks whether a stack is full. (d)\nStackFull()\nThe function uses the variable to represent the pointer to the most recent\nTopOfStack\nposition used on the stack, and the variable to represent the maximum size of the stack.\nMax\nAssume and are global variables.\nTopOfStack Max\nFUNCTION StackFull() RETURNS BOOLEAN\nIF TopOfStack = Max THEN\nRETURN TRUE\nELSE\nRETURN FALSE\nENDIF\nENDFUNCTION\nAn algorithm is required to add a new integer data element to a stack.\nAddInteger\nThe stack is implemented as an array .\nArrayStack\nThe function calls and returns an appropriate message.\nAddInteger() StackFull()\nComplete the pseudocode for the function .\nAddInteger()\nFUNCTION AddInteger(NewInt" }, { "id": "9618-2021-on-41-q01", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 4, "variant": "41", "question_number": 1, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 17, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_41.pdf?download=true", "source_pages": [ 2, 3 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_41.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-on-41-q01-p01.png", "9618-practical-programming/assets/9618-2021-on-41-q01-p02.png" ], "answer": { "status": "available", "id": "9618-2021-on-41-q01", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_41.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_41.pdf?download=true", "source_pages": [ 3, 4, 5, 6, 7, 8 ], "marks": 17 }, "text_excerpt": "Study the following pseudocode for a recursive function. 1\nFUNCTION Unknown(BYVAL X, BYVAL Y : INTEGER) RETURNS INTEGER\nIF X < Y THEN\nOUTPUT X + Y\nRETURN (Unknown(X + 1, Y) * 2)\nELSE\nIF X = Y THEN\nRETURN 1\nELSE\nOUTPUT X + Y\nRETURN (Unknown(X - 1, Y) DIV 2)\nENDIF\nENDIF\nENDFUNCTION\nThe operator returns the integer value after division e.g. would give\nDIV 13 DIV 2 6\nWrite program code to declare the function . (a)\nUnknown()\nSave your program as 1. question\nCopy and paste the program code into in the evidence document. part 1(a)\n[3]\n© UCLES 2021 9618/41/O/N/21\n3\nThe main program needs to run all of the following function calls and output the result (b) three\nof each call:\nUnknown(10, 15)\nUnknown(10, 10)\nUnknown(15, 10)\nFor each of the function calls, the main program needs to: (i) three\n• output the value of the two parameters\n• call the function with those parameters\n• output the return value.\nWrite the program code for the main program.\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(b)(i)\n[3]\nTake a screenshot to show the output from (b)(i). (ii) part\nCopy and paste the screenshot into in the evidence document. part 1(b)(ii)\n[2]\nRewrite the function as an iterative function, . (c)\nUnknown() IterativeUnknown()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(c)\n[7]\nThe iterative function needs to be called times with the same parameters as in (b). (d) three part\nFor each of the function calls, the main program needs to: (i) three\n• output the value of the two parameters\n• call the iterative function with those parameters\n• output the return value.\nAmend the main program to perform these tasks.\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(d)(i)\n[1]\nTake one or more screenshots to show the output of both functions for each set of (ii)\nparameters.\nCopy and paste the screenshot(s) into in the evidence document. part 1(d)(ii)\n[1]\n[Turn over © UCLES 2021 9618/41/O/N/21" }, { "id": "9618-2021-on-41-q02", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 4, "variant": "41", "question_number": 2, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 30, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_41.pdf?download=true", "source_pages": [ 4, 5, 6, 7 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_41.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-on-41-q02-p01.png", "9618-practical-programming/assets/9618-2021-on-41-q02-p02.png", "9618-practical-programming/assets/9618-2021-on-41-q02-p03.png", "9618-practical-programming/assets/9618-2021-on-41-q02-p04.png" ], "answer": { "status": "available", "id": "9618-2021-on-41-q02", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_41.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_41.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12, 13, 14, 15, 16 ], "marks": 30 }, "text_excerpt": "A program, written using object-oriented programming, stores pictures as objects. 2\nThe program stores the dimensions of the picture (width and height), the colour of the frame (e.g.\nblack), and a description of the picture (e.g. flowers).\nThe class has the following attributes and methods.\nPicture\nDescription : STRING // stores a description of the picture\nWidth : INTEGER // stores the width e.g. 30\nHeight : INTEGER // stores the height e.g. 40\nFrameColour : STRING // stores the colour e.g. black\nConstructor() // takes all four values as parameters and\nsets them to the private attributes\nGetDescription() // returns the description of the picture\nGetHeight() // returns the height\nGetWidth() // returns the width\nGetColour() // returns the frame colour\nSetDescription() // takes the new description as a parameter\nand writes the value to description\nThe constructor takes the picture description, frame colour, height, and width as parameters (a)\nand sets these to the private attributes.\nWrite the program code to declare the class and its constructor.\nPicture\nDo not write any other methods.\nUse your language appropriate constructor. All attributes should be private.\nIf you are writing in Python programming language, include attribute declarations using\ncomments.\nSave your program as 2. question\nCopy and paste the program code into in the evidence document. part 2(a)\n[5]\nThe four get methods return the associated attribute, for example, (b)\nGetDescription()\nreturns the description of the picture.\nWrite the get methods. four\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(b)\n[3]\n© UCLES 2021 9618/41/O/N/21\n5\nThe method takes a new description as a parameter, and writes this (c)\nSetDescription()\nvalue to the appropriate attribute.\nWrite the method .\nSetDescription()\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(c)\n[2]\nWrite program code to declare an array of type with 100 elements. (d)\nPicture\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(d)\n[1]\nThe text file stores the data for the pictures in the order: description, width, (e)\nPictures.txt\nheight, colour.\nFor example, for the first picture in the text file:\nis the description\nFlowers\nis the width\n45\nis the height\n50\nis the frame colour.\nblack\nThe data read into the program from the text file is stored in an array of type .\nPicture\nThe main program and the function will need to access the array data.\nThe function :\nReadData()\n• opens the file\nPictures.txt\n• reads the data from the file\n• creates a new object of type for each picture\nPicture\n• writes each object to the array\n• raises an exception if the file cannot be found\n• counts and returns the number of pictures in the array.\nWrite program code for the function .\nReadData()\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(e)\n[8]\nThe main program calls the function . (f)\nReadData()\nWrit" }, { "id": "9618-2021-on-41-q03", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 4, "variant": "41", "question_number": 3, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 34, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_41.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_41.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-on-41-q03-p01.png", "9618-practical-programming/assets/9618-2021-on-41-q03-p02.png", "9618-practical-programming/assets/9618-2021-on-41-q03-p03.png", "9618-practical-programming/assets/9618-2021-on-41-q03-p04.png", "9618-practical-programming/assets/9618-2021-on-41-q03-p05.png" ], "answer": { "status": "available", "id": "9618-2021-on-41-q03", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_41.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_41.pdf?download=true", "source_pages": [ 17, 18, 19, 20, 21, 22, 23 ], "marks": 34 }, "text_excerpt": "An ordered binary tree stores integer data in ascending numerical order. 3\nThe data for the binary tree is stored in a 2D array with the following structure:\nLeftPointer Data RightPointer\nIndex [0] [1] [2]\n1 10 2 [0]\n-1 5 -1 [1]\n-1 16 -1 [2]\nEach row in the table represents one node on the tree.\nThe number represents a null pointer.\n-1\nThe 2D array, , is declared with space for 20 nodes. (a)\nArrayNodes\nEach node has a left pointer, data and right pointer.\nThe program also initialises the:\n• to (null); this points to the first node in the binary tree\nRootPointer -1\n• to ; this points to the first empty node in the array.\nFreeNode 0\nWrite program code to declare , and in the main\nArrayNodes RootPointer FreeNode\nprogram.\nIf you are writing in Python programming language, include attribute declarations using\ncomments.\nSave your program as 3. question\nCopy and paste the program code into in the evidence document. part 3(a)\n[4]\nThe procedure adds a new node to the array . (b)\nAddNode() ArrayNodes\nThe procedure needs to:\n• take the array, root pointer and free node pointer as parameters\n• ask the user to enter the data and read this in\n• add the node to the root pointer if the tree is empty\n• otherwise, follow the pointers to find the position for the data item to be added\n• store the data in the location and update all pointers.\n© UCLES 2021 9618/41/O/N/21\n9\nThere are incomplete statements in the following pseudocode for the procedure . six\nAddNode()\nPROCEDURE AddNode(BYREF ArrayNodes[] : ARRAY OF INTEGER,\nBYREF RootPointer : INTEGER, BYREF FreeNode : INTEGER)\nOUTPUT \"Enter the data\"\nINPUT NodeData\nIF FreeNode <= 19 THEN\n←\n-1 ArrayNodes[FreeNode, 0]\n←\n……………………………………… ArrayNodes[FreeNode, 1]\n←\n-1 ArrayNodes[FreeNode, 2]\nIF RootPointer = ……………………………………… THEN\n←\n0 RootPointer\nELSE\n←\nFALSE Placed\n←\nRootPointer CurrentNode\nWHILE Placed = FALSE\nIF NodeData < ArrayNodes[CurrentNode, 1] THEN\nIF ArrayNodes[CurrentNode, 0] = -1 THEN\n←\n……………………………………… ArrayNodes[CurrentNode, 0]\n←\nTRUE Placed\nELSE\n←\nArrayNodes[CurrentNode, 0] ………………………………………\nENDIF\nELSE\nIF ArrayNodes[CurrentNode, 2] = -1 THEN\n←\nFreeNode ArrayNodes[CurrentNode, 2]\n←\n……………………………………… Placed\nELSE\n←\nArrayNodes[CurrentNode, 2] CurrentNode\nENDIF\nENDIF\nENDWHILE\nENDIF\n←\n……………………………………… + 1 FreeNode\nELSE\nOUTPUT(\"Tree is full\")\nENDIF\nENDPROCEDURE\nWrite for the procedure . program code\nAddNode()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(b)\n[8]\n[Turn over © UCLES 2021 9618/41/O/N/21\n10\nThe procedure outputs the data in each element in , in the order (c)\nPrintAll() ArrayNodes\nthey are stored in the array.\nEach element is printed in a row in the order:\nLeftPointer Data RightPointer\nFor example:\n1 20 -1\n-1 10 -1\nWrite program code for the procedure .\nPrintAll()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(c)\n[4]\nThe main program should loop 10 times, each time calling the procedure . It (d)\nAddNode()\nshould then call the proc" }, { "id": "9618-2021-on-42-q01", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 4, "variant": "42", "question_number": 1, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 17, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_42.pdf?download=true", "source_pages": [ 2, 3 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_42.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-on-42-q01-p01.png", "9618-practical-programming/assets/9618-2021-on-42-q01-p02.png" ], "answer": { "status": "available", "id": "9618-2021-on-42-q01", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_42.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_42.pdf?download=true", "source_pages": [ 3, 4, 5, 6, 7, 8 ], "marks": 17 }, "text_excerpt": "Study the following pseudocode for a recursive function. 1\nFUNCTION Unknown(BYVAL X, BYVAL Y : INTEGER) RETURNS INTEGER\nIF X < Y THEN\nOUTPUT X + Y\nRETURN (Unknown(X + 1, Y) * 2)\nELSE\nIF X = Y THEN\nRETURN 1\nELSE\nOUTPUT X + Y\nRETURN (Unknown(X - 1, Y) DIV 2)\nENDIF\nENDIF\nENDFUNCTION\nThe operator returns the integer value after division e.g. would give\nDIV 13 DIV 2 6\nWrite program code to declare the function . (a)\nUnknown()\nSave your program as 1. question\nCopy and paste the program code into in the evidence document. part 1(a)\n[3]\n© UCLES 2021 9618/42/O/N/21\n3\nThe main program needs to run all of the following function calls and output the result (b) three\nof each call:\nUnknown(10, 15)\nUnknown(10, 10)\nUnknown(15, 10)\nFor each of the function calls, the main program needs to: (i) three\n• output the value of the two parameters\n• call the function with those parameters\n• output the return value.\nWrite the program code for the main program.\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(b)(i)\n[3]\nTake a screenshot to show the output from (b)(i). (ii) part\nCopy and paste the screenshot into in the evidence document. part 1(b)(ii)\n[2]\nRewrite the function as an iterative function, . (c)\nUnknown() IterativeUnknown()\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(c)\n[7]\nThe iterative function needs to be called times with the same parameters as in (b). (d) three part\nFor each of the function calls, the main program needs to: (i) three\n• output the value of the two parameters\n• call the iterative function with those parameters\n• output the return value.\nAmend the main program to perform these tasks.\nSave your program.\nCopy and paste the program code into in the evidence document. part 1(d)(i)\n[1]\nTake one or more screenshots to show the output of both functions for each set of (ii)\nparameters.\nCopy and paste the screenshot(s) into in the evidence document. part 1(d)(ii)\n[1]\n[Turn over © UCLES 2021 9618/42/O/N/21" }, { "id": "9618-2021-on-42-q02", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 4, "variant": "42", "question_number": 2, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 30, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_42.pdf?download=true", "source_pages": [ 4, 5, 6, 7 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_42.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-on-42-q02-p01.png", "9618-practical-programming/assets/9618-2021-on-42-q02-p02.png", "9618-practical-programming/assets/9618-2021-on-42-q02-p03.png", "9618-practical-programming/assets/9618-2021-on-42-q02-p04.png" ], "answer": { "status": "available", "id": "9618-2021-on-42-q02", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_42.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_42.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12, 13, 14, 15, 16 ], "marks": 30 }, "text_excerpt": "A program, written using object-oriented programming, stores pictures as objects. 2\nThe program stores the dimensions of the picture (width and height), the colour of the frame (e.g.\nblack), and a description of the picture (e.g. flowers).\nThe class has the following attributes and methods.\nPicture\nDescription : STRING // stores a description of the picture\nWidth : INTEGER // stores the width e.g. 30\nHeight : INTEGER // stores the height e.g. 40\nFrameColour : STRING // stores the colour e.g. black\nConstructor() // takes all four values as parameters and\nsets them to the private attributes\nGetDescription() // returns the description of the picture\nGetHeight() // returns the height\nGetWidth() // returns the width\nGetColour() // returns the frame colour\nSetDescription() // takes the new description as a parameter\nand writes the value to description\nThe constructor takes the picture description, frame colour, height, and width as parameters (a)\nand sets these to the private attributes.\nWrite the program code to declare the class and its constructor.\nPicture\nDo not write any other methods.\nUse your language appropriate constructor. All attributes should be private.\nIf you are writing in Python programming language, include attribute declarations using\ncomments.\nSave your program as 2. question\nCopy and paste the program code into in the evidence document. part 2(a)\n[5]\nThe four get methods return the associated attribute, for example, (b)\nGetDescription()\nreturns the description of the picture.\nWrite the get methods. four\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(b)\n[3]\n© UCLES 2021 9618/42/O/N/21\n5\nThe method takes a new description as a parameter, and writes this (c)\nSetDescription()\nvalue to the appropriate attribute.\nWrite the method .\nSetDescription()\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(c)\n[2]\nWrite program code to declare an array of type with 100 elements. (d)\nPicture\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(d)\n[1]\nThe text file stores the data for the pictures in the order: description, width, (e)\nPictures.txt\nheight, colour.\nFor example, for the first picture in the text file:\nis the description\nFlowers\nis the width\n45\nis the height\n50\nis the frame colour.\nblack\nThe data read into the program from the text file is stored in an array of type .\nPicture\nThe main program and the function will need to access the array data.\nThe function :\nReadData()\n• opens the file\nPictures.txt\n• reads the data from the file\n• creates a new object of type for each picture\nPicture\n• writes each object to the array\n• raises an exception if the file cannot be found\n• counts and returns the number of pictures in the array.\nWrite program code for the function .\nReadData()\nSave your program.\nCopy and paste the program code into in the evidence document. part 2(e)\n[8]\nThe main program calls the function . (f)\nReadData()\nWrit" }, { "id": "9618-2021-on-42-q03", "subject": "9618", "year": 2021, "session": "Oct/Nov", "session_code": "on", "paper": 4, "variant": "42", "question_number": 3, "topic_number": null, "topic": "Practical programming", "topic_slug": "9618-practical-programming", "marks": 34, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_qp_42.pdf?download=true", "source_pages": [ 8, 9, 10, 11, 12 ], "local_pdf": "_source-pdfs/2021-oct-nov/qp/9618_w21_qp_42.pdf", "image_paths": [ "9618-practical-programming/assets/9618-2021-on-42-q03-p01.png", "9618-practical-programming/assets/9618-2021-on-42-q03-p02.png", "9618-practical-programming/assets/9618-2021-on-42-q03-p03.png", "9618-practical-programming/assets/9618-2021-on-42-q03-p04.png", "9618-practical-programming/assets/9618-2021-on-42-q03-p05.png" ], "answer": { "status": "available", "id": "9618-2021-on-42-q03", "html": "9618-practical-programming/answers.html", "source_pdf": "_source-pdfs/2021-oct-nov/ms/9618_w21_ms_42.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2021-Oct-Nov/9618_w21_ms_42.pdf?download=true", "source_pages": [ 17, 18, 19, 20, 21, 22, 23 ], "marks": 34 }, "text_excerpt": "An ordered binary tree stores integer data in ascending numerical order. 3\nThe data for the binary tree is stored in a 2D array with the following structure:\nLeftPointer Data RightPointer\nIndex [0] [1] [2]\n1 10 2 [0]\n-1 5 -1 [1]\n-1 16 -1 [2]\nEach row in the table represents one node on the tree.\nThe number represents a null pointer.\n-1\nThe 2D array, , is declared with space for 20 nodes. (a)\nArrayNodes\nEach node has a left pointer, data and right pointer.\nThe program also initialises the:\n• to (null); this points to the first node in the binary tree\nRootPointer -1\n• to ; this points to the first empty node in the array.\nFreeNode 0\nWrite program code to declare , and in the main\nArrayNodes RootPointer FreeNode\nprogram.\nIf you are writing in Python programming language, include attribute declarations using\ncomments.\nSave your program as 3. question\nCopy and paste the program code into in the evidence document. part 3(a)\n[4]\nThe procedure adds a new node to the array . (b)\nAddNode() ArrayNodes\nThe procedure needs to:\n• take the array, root pointer and free node pointer as parameters\n• ask the user to enter the data and read this in\n• add the node to the root pointer if the tree is empty\n• otherwise, follow the pointers to find the position for the data item to be added\n• store the data in the location and update all pointers.\n© UCLES 2021 9618/42/O/N/21\n9\nThere are incomplete statements in the following pseudocode for the procedure . six\nAddNode()\nPROCEDURE AddNode(BYREF ArrayNodes[] : ARRAY OF INTEGER,\nBYREF RootPointer : INTEGER, BYREF FreeNode : INTEGER)\nOUTPUT \"Enter the data\"\nINPUT NodeData\nIF FreeNode <= 19 THEN\n←\n-1 ArrayNodes[FreeNode, 0]\n←\n……………………………………… ArrayNodes[FreeNode, 1]\n←\n-1 ArrayNodes[FreeNode, 2]\nIF RootPointer = ……………………………………… THEN\n←\n0 RootPointer\nELSE\n←\nFALSE Placed\n←\nRootPointer CurrentNode\nWHILE Placed = FALSE\nIF NodeData < ArrayNodes[CurrentNode, 1] THEN\nIF ArrayNodes[CurrentNode, 0] = -1 THEN\n←\n……………………………………… ArrayNodes[CurrentNode, 0]\n←\nTRUE Placed\nELSE\n←\nArrayNodes[CurrentNode, 0] ………………………………………\nENDIF\nELSE\nIF ArrayNodes[CurrentNode, 2] = -1 THEN\n←\nFreeNode ArrayNodes[CurrentNode, 2]\n←\n……………………………………… Placed\nELSE\n←\nArrayNodes[CurrentNode, 2] CurrentNode\nENDIF\nENDIF\nENDWHILE\nENDIF\n←\n……………………………………… + 1 FreeNode\nELSE\nOUTPUT \"Tree is full\"\nENDIF\nENDPROCEDURE\nWrite for the procedure . program code\nAddNode()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(b)\n[8]\n[Turn over © UCLES 2021 9618/42/O/N/21\n10\nThe procedure outputs the data in each element in , in the order (c)\nPrintAll() ArrayNodes\nthey are stored in the array.\nEach element is printed in a row in the order:\nLeftPointer Data RightPointer\nFor example:\n1 20 -1\n-1 10 -1\nWrite program code for the procedure .\nPrintAll()\nSave your program.\nCopy and paste the program code into in the evidence document. part 3(c)\n[4]\nThe main program should loop 10 times, each time calling the procedure . It (d)\nAddNode()\nshould then call the proce" }, { "id": "9618-2022-mj-31-q01", "subject": "9618", "year": 2022, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 1, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "source_pages": [ 2, 3 ], "local_pdf": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2022-mj-31-q01-p01.png", "9618-topic-20-further-programming/assets/9618-2022-mj-31-q01-p02.png" ], "answer": { "status": "available", "id": "9618-2022-mj-31-q01", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2022-may-june/ms/9618_s22_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_ms_31.pdf?download=true", "source_pages": [ 4 ], "marks": 8 }, "text_excerpt": "Data types can be defined using pseudocode. 1\nThe data type, , is defined in pseudocode as:\nLibraryRecord\nTYPE LibraryRecord\nDECLARE Title : STRING\nDECLARE Fiction : BOOLEAN\nDECLARE Author : STRING\nDECLARE NumberOfCopies : INTEGER\nENDTYPE\nA variable, , is declared in pseudocode as:\nLibraryBook\nDECLARE LibraryBook : LibraryRecord\nWrite statements to assign: (a) pseudocode\n• to of\nA Level Computer Science Title LibraryBook\n• to of .\nFALSE Fiction LibraryBook\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n............................................................................................................................................. [2]\nThe type definition for is changed. (b)\nLibraryRecord\nThe value for must be between and inclusive. (i)\nNumberOfCopies 1 10\nWrite the updated line of from the type definition of to pseudocode\nLibraryRecord\nimplement the change.\n...........................................................................................................................................\n..................................................................................................................................... [1]\nEvery copy of every book is now uniquely identified by an accession number, (ii)\n, as it is added to the library. Each library record will include one or\nAccessionNumber\nmore accession numbers. Each accession number is an integer.\nWrite the extra line of needed in the type definition of . pseudocode\nLibraryRecord\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [2]\n© UCLES 2022 9618/31/M/J/22\n3\nA record is a user-defined composite data type. (c)\nExplain what is meant by a type. user-defined composite data\nInclude an example of user-defined composite data type in your answer. another\n...................................................................................................................................................\n...................................................................................................................................................\n....................................................." }, { "id": "9618-2022-mj-31-q02", "subject": "9618", "year": 2022, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 2, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 6, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "source_pages": [ 4, 5 ], "local_pdf": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2022-mj-31-q02-p01.png", "9618-topic-20-further-programming/assets/9618-2022-mj-31-q02-p02.png" ], "answer": { "status": "available", "id": "9618-2022-mj-31-q02", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2022-may-june/ms/9618_s22_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_ms_31.pdf?download=true", "source_pages": [ 4 ], "marks": 6 }, "text_excerpt": "A declarative language is used to represent the following facts about cats. 2\n01 type(leopard, wild).\n02 type(lion, wild).\n03 type(cheetah, wild).\n04 type(savannah, hybrid).\n05 type(persian, domestic).\n06\n07 hair(leopard, medium).\n08 hair(lion, short).\n09 hair(cheetah, medium).\n10 hair(savannah, medium).\n11 hair(persian, long).\n12\n13 spots(leopard, yes).\n14 spots(lion, no).\n15 spots(cheetah, yes).\n16 spots(savannah, yes).\n17 spots(persian, no).\nThese clauses have the following meaning:\nClause Meaning\nA leopard is a type of wild cat. 01\nA lion has short hair. 08\nA savannah has spots. 16\n© UCLES 2022 9618/31/M/J/22\n5\nMore facts are to be included. A is a wild cat with short hair. (a) caracal\nWrite the additional clauses to record these facts.\n.............................................................................................................................................\n18\n.............................................................................................................................................\n19\n[2]\nUsing the variable , the goal: (b)\nCat\nhair(Cat, medium)\nreturns\nCat = leopard, cheetah, savannah\nWrite the result returned by the goal:\nhair(Cat, long)\n................................................................................................................................. [1]\nCat =\nWrite the goal, using the variable , to find all the domestic cats. (c) (i)\nPet\n...........................................................................................................................................\n..................................................................................................................................... [1]\nWrite the goal, using the variable , to find all the wild cats with spots. (ii)\nWildSpotty\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [2]\n[Turn over © UCLES 2022 9618/31/M/J/22" }, { "id": "9618-2022-mj-31-q03", "subject": "9618", "year": 2022, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 3, "topic_number": 14, "topic": "Communication and internet technologies", "topic_slug": "9618-topic-14-communication-and-internet-technologies", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "source_pages": [ 6 ], "local_pdf": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf", "image_paths": [ "9618-topic-14-communication-and-internet-technologies/assets/9618-2022-mj-31-q03-p01.png" ], "answer": { "status": "available", "id": "9618-2022-mj-31-q03", "html": "9618-topic-14-communication-and-internet-technologies/answers.html", "source_pdf": "_source-pdfs/2022-may-june/ms/9618_s22_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_ms_31.pdf?download=true", "source_pages": [ 5 ], "marks": 8 }, "text_excerpt": "Data can be sent over networks using either circuit switching or packet switching. 3\nDescribe both methods of data transmission. Include a different advantage and disadvantage for\neach method.\nCircuit switching ...............................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\nAdvantage ........................................................................................................................................\n..........................................................................................................................................................\nDisadvantage ...................................................................................................................................\n..........................................................................................................................................................\nPacket switching ..............................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\nAdvantage ........................................................................................................................................\n..........................................................................................................................................................\nDisadvantage ...................................................................................................................................\n..........................................................................................................................................................\n[8]\n© UCLES 2022 9618/31/M/J/22" }, { "id": "9618-2022-mj-31-q04", "subject": "9618", "year": 2022, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 4, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 6, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "source_pages": [ 7 ], "local_pdf": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2022-mj-31-q04-p01.png" ], "answer": { "status": "available", "id": "9618-2022-mj-31-q04", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2022-may-june/ms/9618_s22_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_ms_31.pdf?download=true", "source_pages": [ 6 ], "marks": 6 }, "text_excerpt": "Reduced Instruction Set Computers (RISC) and Complex Instruction Set Computers (CISC) are 4\ntwo types of processor.\nDescribe what is meant by and processors. (a) RISC CISC\nRISC .........................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\nCISC .........................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n[4]\nIdentify differences between RISC and CISC processors. (b) two\n1 ................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n2 ................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n[2]\n[Turn over © UCLES 2022 9618/31/M/J/22" }, { "id": "9618-2022-mj-31-q05", "subject": "9618", "year": 2022, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 5, "topic_number": 16, "topic": "System software", "topic_slug": "9618-topic-16-system-software", "marks": 12, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "source_pages": [ 8, 9 ], "local_pdf": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf", "image_paths": [ "9618-topic-16-system-software/assets/9618-2022-mj-31-q05-p01.png", "9618-topic-16-system-software/assets/9618-2022-mj-31-q05-p02.png" ], "answer": { "status": "available", "id": "9618-2022-mj-31-q05", "html": "9618-topic-16-system-software/answers.html", "source_pdf": "_source-pdfs/2022-may-june/ms/9618_s22_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_ms_31.pdf?download=true", "source_pages": [ 7 ], "marks": 12 }, "text_excerpt": "Part of a program’s calculations uses the integer variables , , , and . 5\nj k m n p\nj = 3\nk = 2\nm = 10\nn = (j + k)/(j - k)\np = m * (m - j * k)\nWrite the Reverse Polish Notation (RPN) for the expression: (a)\n(j + k)/(j - k)\n............................................................................................................................................. [2]\nShow the changing contents of the stack as the value for is calculated from its RPN (b) (i)\np\nexpression:\nm m j k * - *\n[4]\nDescribe the main steps in the evaluation of this RPN expression using a stack. (ii)\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n..................................................................................................................................... [4]\n© UCLES 2022 9618/31/M/J/22\n9\nState uses of a stack. (c) two other\n1 ................................................................................................................................................\n...................................................................................................................................................\n2 ................................................................................................................................................\n...................................................................................................................................................\n[2]" }, { "id": "9618-2022-mj-31-q06", "subject": "9618", "year": 2022, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 6, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 6, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "source_pages": [ 9 ], "local_pdf": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2022-mj-31-q06-p01.png" ], "answer": { "status": "available", "id": "9618-2022-mj-31-q06", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2022-may-june/ms/9618_s22_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_ms_31.pdf?download=true", "source_pages": [ 8 ], "marks": 6 }, "text_excerpt": "A virtual machine is used to emulate a new computer system. 6\nDescribe benefits and limitation of using a virtual machine for this purpose. two one\nBenefit 1 ...........................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\nBenefit 2 ...........................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\nLimitation ..........................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n..........................................................................................................................................................\n[6]\n[Turn over © UCLES 2022 9618/31/M/J/22" }, { "id": "9618-2022-mj-31-q07", "subject": "9618", "year": 2022, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 7, "topic_number": 20, "topic": "Further programming", "topic_slug": "9618-topic-20-further-programming", "marks": 11, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "source_pages": [ 10, 11 ], "local_pdf": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf", "image_paths": [ "9618-topic-20-further-programming/assets/9618-2022-mj-31-q07-p01.png", "9618-topic-20-further-programming/assets/9618-2022-mj-31-q07-p02.png" ], "answer": { "status": "available", "id": "9618-2022-mj-31-q07", "html": "9618-topic-20-further-programming/answers.html", "source_pdf": "_source-pdfs/2022-may-june/ms/9618_s22_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_ms_31.pdf?download=true", "source_pages": [ 9, 10 ], "marks": 11 }, "text_excerpt": "A program is to be written using Object-Oriented Programming (OOP) for a shop that sells knitting 7\nyarn. There are three types of yarn: acrylic, wool or mix.\nThe following data are stored for each type.\n• Name\n• Colour\n• Batch code\n• Weight\n• Number of balls of yarn in stock (can be edited)\n• Type of yarn\nThe following statements apply to yarn.\n• Acrylic can be soft or not soft.\n• Wool can be lamb, merino or alpaca.\n• Mix contains a percentage of acrylic.\nEach type of yarn has a method that will display all the information about the yarn.\nComplete this class inheritance diagram to show the properties, and inheritance. (a) methods\nYarn\nName: STRING\nColour: STRING\nBatchCode: STRING\nWeight: INTEGER\nNumberBalls: INTEGER\nType: STRING\nConstructor()\nEditNumberBalls()\nYarnInfo()\nAcrylic Wool Mix\nPercentage: INTEGER\nConstructor() .......................................... ..........................................\nYarnInfo()\nConstructor() Constructor()\n.......................................... ..........................................\n[5]\n© UCLES 2022 9618/31/M/J/22\n11\nDescribe what is meant by the terms properties, and inheritance. (b) methods\nProperties .................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\nMethods ....................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\nInheritance ................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n...................................................................................................................................................\n[6]\n[Turn over © UCLES 2022 9618/31/M/J/22" }, { "id": "9618-2022-mj-31-q08", "subject": "9618", "year": 2022, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 8, "topic_number": 17, "topic": "Security", "topic_slug": "9618-topic-17-security", "marks": 8, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "source_pages": [ 12, 13 ], "local_pdf": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf", "image_paths": [ "9618-topic-17-security/assets/9618-2022-mj-31-q08-p01.png", "9618-topic-17-security/assets/9618-2022-mj-31-q08-p02.png" ], "answer": { "status": "available", "id": "9618-2022-mj-31-q08", "html": "9618-topic-17-security/answers.html", "source_pdf": "_source-pdfs/2022-may-june/ms/9618_s22_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_ms_31.pdf?download=true", "source_pages": [ 10 ], "marks": 8 }, "text_excerpt": "A message is to be sent securely. Software uses a key to encrypt the message before it is sent. 8\nGive reasons for using key cryptography. (a) (i) two\n1 ........................................................................................................................................\n...........................................................................................................................................\n2 ........................................................................................................................................\n...........................................................................................................................................\n[2]\nGive methods of key cryptography that can be used. (ii) two\n1 ........................................................................................................................................\n2 ........................................................................................................................................\n[2]\nWhen there is a secure exchange of key(s), the message is sent. (b)\nThe use of quantum cryptography is being considered for the secure exchange.\nState possible benefits of using quantum cryptography. (i) two\n1 ........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n2 ........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n[2]\nState possible drawbacks of using quantum cryptography. (ii) two\n1 ........................................................................................................................................\n...........................................................................................................................................\n...........................................................................................................................................\n2 ........................................................................................................................................\n...........................................................................................................................................\n...................................................................................................................................." }, { "id": "9618-2022-mj-31-q09", "subject": "9618", "year": 2022, "session": "May/June", "session_code": "mj", "paper": 3, "variant": "31", "question_number": 9, "topic_number": 15, "topic": "Hardware and virtual machines", "topic_slug": "9618-topic-15-hardware-and-virtual-machines", "marks": 10, "source_pdf": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_qp_31.pdf?download=true", "source_pages": [ 14, 15, 16 ], "local_pdf": "_source-pdfs/2022-may-june/qp/9618_s22_qp_31.pdf", "image_paths": [ "9618-topic-15-hardware-and-virtual-machines/assets/9618-2022-mj-31-q09-p01.png", "9618-topic-15-hardware-and-virtual-machines/assets/9618-2022-mj-31-q09-p02.png", "9618-topic-15-hardware-and-virtual-machines/assets/9618-2022-mj-31-q09-p03.png" ], "answer": { "status": "available", "id": "9618-2022-mj-31-q09", "html": "9618-topic-15-hardware-and-virtual-machines/answers.html", "source_pdf": "_source-pdfs/2022-may-june/ms/9618_s22_ms_31.pdf", "source_pdf_url": "https://pastpapers.co/api/file/caie/A-Level/Computer%20Science%20%28for%20first%20examination%20in%202021%29%20%289618%29/2022-May-June/9618_s22_ms_31.pdf?download=true", "source_pages": [ 11 ], "marks": 10 }, "text_excerpt": "The table shows assembly language instructions for a processor that has one general purpose 9\nregister, the Accumulator (ACC).\nInstruction Explanation\nLabel Opcode Operand\nLoad the number n to ACC\nLDM #n\nLoad the contents of the given address to ACC\nLDD
\nThe address to be used is at the given address\nLDI
\nLoad the contents of this second address to ACC\nAdd the contents of the given address to the ACC\nADD
\nStore the contents of the ACC at the given address\nSTO
\nGives a symbolic address