Edexcel GCSE Computer Science (1CP2) Exam Questions

Award one mark for:

• Several/multiple machine code instructions (1)

The answer must refer to instructions.

Do not accept machine code on its own.

Do not accept binary on its own.

Do not accept 'one or more machine code instructions' as it does not show that one statement becomes several instructions.

Do not accept assembly code/compiled code/low-level code on their own.

Do not accept 'a line of code'/'a statement' as this repeats the question.

Award one mark for any of the following:

• Object code (1)
• Machine code (1)
• Executable code / an executable (1)

Allow object file.

Do not accept source code.

Do not accept high-level code.

Award up to two marks for a linked description such as:

• Statements are written using words/phrases that look like English or maths (1) so the code is easier to read/understand/write (1)
• One statement is translated into several machine code instructions (1) so programs are shorter to write than in a low-level language (1)
• High-level languages provide built-in data structures such as arrays/lists/records (1) so a collection of data items can be stored and accessed under one name (1)

Do not accept responses that only give a benefit or drawback, such as 'it is easier to learn', with no characteristic.

Do not accept 'it is easier than a low-level language' without saying what the characteristic is.

Award up to two marks for a linked explanation such as:

• The compiler produces object code/machine code for the whole program (1) so there is no complete executable until every line has been translated (1)
• The compiler translates all the source code before producing the object code (1) so the program cannot start until translation has finished (1)
• The compiler checks the whole program for errors during translation (1) so all of the source code must be read before an executable can be produced (1)

For both marks, the expansion must follow/associate with the statement.

Allow 'in one go'/'all at once' for the translation point, but this does not earn the second mark unless it is linked to why the program cannot be executed until translation has finished.

A statement that the whole program is translated, with no linked reason about when the program can be executed, earns 1 mark only.

Do not accept 'a compiler is faster' or 'compiled code runs faster' on its own; this does not explain why translation must finish before execution.

Do not accept 'it translates and runs the program one line at a time', as this describes an interpreter.

Indicative content

Ease of learning, use and debug

• High-level language statements are written in English-like words and mathematical symbols, so the students can read the quiz game code and understand what each line does.
• The language is easier to learn than a low-level language, so students who are new to programming can start writing the quiz game quickly.
• Errors are easier to find and fix because the code is readable; for example, the students can check a line that updates a score against the rule they intended.
• The students do not need to know how the processor carries out each statement, so they can concentrate on the quiz questions and rules.

Data structures

• High-level languages provide lists or arrays, so the names and scores of all the players can be stored under one name and processed with a loop.
• A record can store a player's name and score as one item; in some languages a dictionary or class can be used instead, which keeps related data together.
• Using a data structure makes the code shorter and easier to understand than separate variables for every player's name and score.

Built-in functions and library routines

• High-level languages provide built-in functions such as print and input, so the students can display a question and read a player's answer without writing the underlying code.
• Library routines such as a random number generator can be used to choose quiz questions, saving the students time.
• String-handling routines can check or compare a player's answer, so the students do not have to write these routines themselves.
• Reusing tested routines reduces the amount of code the students write and can reduce errors in the quiz game.

Levels

• Level 0 (0 marks): No rewardable content.
• Level 1 (1–2 marks): Basic, independent points are made, showing elements of understanding of key concepts/principles of computer science. (AO1) The discussion will contain basic information with little linkage between points made or application to the context. (AO2)
• Level 2 (3–4 marks): Demonstrates adequate understanding of key concepts/principles of computer science. (AO1) The discussion shows some linkages and lines of reasoning with some structure and application to the context. (AO2)
• Level 3 (5–6 marks): Demonstrates comprehensive understanding of key concepts/principles of computer science to support the discussion being presented. (AO1) The discussion is well developed, with sustained lines of reasoning that are coherent and logically structured, and which clearly apply to the context. (AO2)

Additional guidance: Credit only points applied to the quiz game and the students; comparison with low-level languages is not required, but a correct contrast may support a point if it is applied. Do not award generic claims such as 'high-level programs run faster', 'work on any computer' or 'students do not need to learn syntax' unless they are justified for the quiz game.

Level 3 responses must cover all three bullet areas with linked reasoning that explains why the characteristic helps the students finish the game quickly with few errors; an answer covering only two bullet areas is limited to Level 2. Do not award the idea that high-level code is already machine code or is understood directly by the processor. Accept dictionaries or classes as equivalents of records.