Pearson pseudocode: variables, selection and loops

Paper 1 questions may show algorithms in Pearson's own pseudocode (the command set in Appendix 5 of the specification). You need to read it fluently. You may write your own answers in any clear pseudocode or in a programming language.

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Variables, input and output

SET total TO 0 assigns a value. A constant is declared with CONST and set once.
RECEIVE mark FROM (INTEGER) KEYBOARD reads input and says its data type.
SEND total TO DISPLAY outputs a value. The & operator joins strings, so SEND 'Fred' & age TO DISPLAY with age 18 shows Fred18.
Operators: + - * / as usual, MOD (remainder) and DIV (whole-number division). Comparisons use = for equal and <> for not equal. Logic uses AND, OR and NOT. Comments start with #.

Selection

IF ... THEN, an optional ELSE, then END IF:
RECEIVE mark FROM (INTEGER) KEYBOARD
IF mark >= 50 THEN
SEND 'Pass' TO DISPLAY
ELSE
SEND 'Fail' TO DISPLAY
END IF
Python equivalent: if mark >= 50: print("Pass") else: print("Fail").

Four kinds of loop

FOR ... STEP -1 counts down. FOR EACH item FROM list DO ... END FOREACH visits every item.
PseudocodeWhat it doesPython
WHILE condition DO ... END WHILEChecks first; may run zero timeswhile condition:
REPEAT ... UNTIL conditionRuns at least once; stops when the condition is TrueNo direct equivalent
REPEAT 5 TIMES ... END REPEATRuns a fixed number of timesfor i in range(5):
FOR i FROM 1 TO 10 DO ... END FORCounts from 1 to 10, including 10for i in range(1, 11):

Tracing pseudocode

Follow it line by line, exactly as for code:
SET total TO 0
FOR count FROM 1 TO 4 DO
SET total TO total + count
END FOR
SEND total TO DISPLAY
total goes 1, 3, 6, 10, so it outputs 10. Note that FOR ... FROM 1 TO 4 includes 4, unlike range(1, 4) in Python.
Worked example

What is output by this pseudocode?
SET number TO 1
REPEAT
SET number TO number * 3
UNTIL number > 50
SEND number TO DISPLAY

  1. REPEAT runs the body first: number becomes 3, then 9, 27 and 81.
  2. After each pass the condition is checked: 81 > 50 is the first True result.
  3. The loop ends and 81 is sent to the display.

Answer: 81

Key idea

Pearson pseudocode uses SET ... TO for assignment, RECEIVE and SEND for input and output, & to join strings, MOD and DIV, IF ... THEN ... ELSE ... END IF, and WHILE, REPEAT ... UNTIL, REPEAT n TIMES and FOR ... FROM ... TO loops. FOR includes its end value.

Key words
Selection
Choosing which code runs using a condition, such as if, elif and else.
Assignment
Storing a value in a variable, such as total = 0.
MOD and DIV
Remainder and integer division. Python: % and //
IF ... THEN ... ELSE ... END IF
Selection. Python: if ...: then else:
SET total TO 0
Assignment. Python: total = 0
Constant
A named value that does not change while the program runs.

All GCSE and International GCSE Computer Science key terms and definitions →

Quick check

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Extra practice

2 more questions

Try each one, then tap to check.

  1. What is output?
    SET count TO 1
    REPEAT 4 TIMES
    SET count TO count + 3
    END REPEAT
    SEND count TO DISPLAY

    Show the answer

    Answer: 13

    count: 1 → 4 → 7 → 10 → 13.

  2. What is output?
    SET n TO 10
    WHILE n < 5 DO
    SET n TO n - 1
    END WHILE
    SEND n TO DISPLAY

    Show the answer

    Answer: 10

    10 < 5 is false at the start, so the loop body never runs and n stays 10.

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Sources and references

Checked by the GCSE-ready editorial team, 17 October 2026. Last updated 2 October 2026. Spotted a mistake? Tell us and we will fix it.

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