AQA A-Level Computer Science AS Paper 1, June 2025: Question 10

✅ Correct Answer

Any one of the following terms:

• Subroutine
• Procedure
• Function
• Method
• Also accepted: Module / block of code

💡 Key Knowledge

A hierarchy chart (structure chart) breaks down a system top-down into smaller, manageable units:

• Each box represents a discrete subprogram / subroutine.
• Each connecting line represents a call relationship (the upper box calls the lower box).
• Hierarchy charts show program structure, not flow of control, decisions, or loops.

🧠 Exam Technique

Use precise formal computing terms. While "module" or "block of code" is allowed in the mark scheme, answering with subroutine, procedure, or function is standard textbook terminology that guarantees marks across all exam boards.

❌ Common Errors

• Confusing structure charts with flowcharts: Stating that a box represents a "step", "instruction", "process", or "condition".
• Stating that a box is a "variable", "parameter", or "data structure".

✅ Correct Answers

For boxes (a) and (b) (in either order):

• 10.2: PirateWalks (or PirateDigs )
• 10.3: PirateDigs (or PirateWalks )

Note: The mark scheme ignores casing and spaces, but rejects duplicate entries.

💡 Key Knowledge: Code Tracing

In the pre-released Skeleton Program, inspecting the subroutine GetPirateAction reveals how it delegates tasks:

• It prompts for an action or chooses an action for the pirate.
• If the pirate walks, it calls PirateWalks(...) .
• If the pirate digs, it calls PirateDigs(...) .
• Because both are invoked directly by GetPirateAction , they sit as direct child nodes under it.

🧠 Exam Technique

When revising the Skeleton Program before Paper 1:

• Construct a full subroutine call graph (who calls whom). Questions testing the modular layout of the Skeleton Program appear frequently.
• Ensure you don't repeat the same identifier in both 10.2 and 10.3.

❌ Common Errors

• Writing subroutines called from the main program rather than from GetPirateAction (e.g., writing DisplayGrid or CheckGameOver ).
• Writing the same subroutine name in both boxes, forfeiting the mark for 10.3.

✅ Correct Answer

Design (or "During the design stage")

💡 Key Knowledge: SDLC Stages

• Analysis: Defining requirements, user interviews, formulating problem specification.
• Design: Planning algorithms, structure charts, data structures, UI mockups, and validation rules before coding.
• Implementation (Coding): Translating designs into source code.
• Testing: Verifying code with normal, boundary, and erroneous data.
• Evaluation & Maintenance: Assessing criteria against user needs and fixing post-deployment issues.

🧠 Exam Technique: Single Clear Term

Notice the explicit mark scheme instruction: "R. more than one stage given". Writing "Analysis and Design" or "Design / Implementation" scores 0 marks. When asked to "State the stage", give exactly one definitive stage.

❌ Common Errors

• Writing "Implementation" or "Coding" — hierarchy charts are a planning tool created prior to writing program code.
• Hedging bets by naming multiple stages (e.g. "Planning and Analysis" or "Design/Development").