AQA A-Level Computer Science AS Paper 1, June 2025: Question 9

✅ Acceptable Answers

• Pirate
• A. PirateRecord (acceptable variant depending on language version)
• Java only: MoveCheckRecord

💡 Key Knowledge

A data structure storing values of more than one data type is known as a heterogeneous data structure (typically a Record, Struct, or Class).

• For example, a pirate might hold an integer coordinate ( X , Y ), a boolean flag, and a string name.

🧠 Exam Technique

• Identifier only: Write only the name of the data structure. Do not append parentheses () , brackets [] , or type declarations.
• Case sensitivity and spacing are ignored by examiners, but spelling must be 100% accurate.

❌ Common Errors

• Adding syntax: Writing Pirate() , new Pirate , or Dim Pirate — the mark scheme explicitly notes "R. if any additional code".
• Misspelling: Typing Priate loses the mark entirely ("R. if spelt incorrectly").
• Naming an array of integers (e.g. Map ), which only holds single-type elements.

✅ Acceptable Answers

Any one of the following identifiers:

• Map
• HiddenMap
• MapSize
• A. MapSizeRecord

💡 Key Knowledge

A structure storing values of only one built-in type is homogeneous (e.g. an array of Char , String , or Integer ).

• Map / HiddenMap are 2D arrays/grids holding characters or strings representing grid tiles.
• Every element in the grid is of the exact same primitive/built-in type.

🧠 Exam Technique

• Look at the top of the program or main module where the board / game grid is declared.
• Notice the keyword built-in: Ensure the elements are standard primitive types (e.g. Char , Integer ) rather than custom programmer-defined records.

❌ Common Errors

• Writing array indices like Map[][] or Map(,) — this counts as additional code and loses the mark.
• Writing an array of records (e.g. Pirates array), because its elements are composite/custom records, not a built-in data type.