Cambridge Pseudocode Standards & Identifier Tables

In Cambridge International examinations, algorithms written in pseudocode must adhere strictly to the standardized conventions defined in the syllabus. This ensures unambiguous readability and consistency across all computing tasks.

1. Golden Rules of Cambridge Pseudocode

1. Keywords in UPPERCASE

All language reserved words and control structures must be capitalized:

• Declarations: DECLARE, CONSTANT
• Input / Output: INPUT, OUTPUT
• Selection: IF, THEN, ELSE, ENDIF, CASE, OF, OTHERWISE, ENDCASE
• Iteration: FOR, TO, STEP, NEXT, WHILE, DO, ENDWHILE, REPEAT, UNTIL
• Subroutines: PROCEDURE, ENDPROCEDURE, FUNCTION, RETURNS, ENDFUNCTION, CALL
• Boolean Literals: TRUE, FALSE

2. Assignment Arrow (<-)

In Cambridge pseudocode, the assignment operator is the arrow <-:

Counter <- Counter + 1
TaxRate <- 0.175
IsValid <- TRUE

Exam Warning: Using = for assignment (e.g., Counter = Counter + 1) is an error. The = sign is reserved exclusively as a relational operator for comparing equality.

3. Meaningful Identifiers

Variable, constant, and subroutine names must be self-documenting:

• Good: TotalPrice, StudentName, Index, IsRegistered
• Often unclear without context: x, temp1, a, foo

2. Standard Cambridge Data Types

3. The Identifier Table

An identifier table is a useful design aid for recording names, types and purposes:

Written practice and self-review

A student wrote the following Cambridge pseudocode declarations:

DECLARE 1stScore : INT
DECLARE Total Score : REAL

Identify the three syntax errors in these declarations according to Cambridge pseudocode standards and explain how each should be corrected.

Write an explanation before checking the theory. Check that each claim answers the question, uses the correct concept and explains why it applies. Discuss uncertain points with a teacher. The structured exercise below checks specific facts; it does not automatically mark this explanation.

Maintainability practice

Use meaningful identifiers, suitable comments, procedures/functions for coherent tasks and named constants for fixed values. In a ticket program, replace x with TicketTotal and a repeated price literal with a named constant; indent the body of each selection and loop. Explain why a comment such as “ignore the terminating -1” is more helpful than repeating “add one” beside Count <- Count + 1. Short conventional loop names can still be clear in context.