Categories: All Variables and Constants  String manipulation  Builtin functions  Input and output  Arrays  Conditional logic  Repetition / Iteration  Functions / Procedures 


This resource is designed as a quick reference or revision guide. It has not been endorsed by any exam boards. If you spot any mistakes, please let me know and I'll fix them asap.


This website aims to give a quick reference for VB.NET, Python, C# and pseudocode and is aimed primarily at teachers & students working towards a GCSE in Computer Science

VB.NET, Python and C# are programming languages designed to be understood and followed by computers. Pseudocode is not a programming language: it's written to be understood by humans so that they can turn it into any programming language.

Each exam board has published a document saying how they'll write pseudocode in their exams. The whole idea of syntax (a set of rules) for pseudocode is silly - it's not designed to be a programming language that is run by a computer. With this in mind, all exam boards state that you don't have to follow the syntax for 'their' version of pseudocode when you write out your own algorithms, but you should be able to understand their version of pseudocode when reading an algorithm in an exam.

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Create and use a procedure with parameters

A procedure is a section of code that has a name, that you can re-use to do something useful.

Parameters are variables that allow you to send data to the procedure to customise what it does or how it works. 

A procedure definition is the code that tells the computer what to do whenever that procedure runs. The parameters are the variables named in brackets after the procedure name.

The procedure wont actually do anything until you call it.

This example defines a procedure which will display a random number. It has two parameters which allow you to set the minimum and maximum number the random number will be between.  

This procedure is called to show a random number between 10 and 20 and then called again to choose a random number between 50 and 100.

# Define the procedure PROCEDURE ShowRandomBetween(min, max) BEGIN PROCEDURE INTEGER n SET n TO RANDOM(max - min) + min SEND n TO DISPLAY END PROCEDURE # Call the procedure ShowRandomBetween(10, 20) ShowRandomBetween(50, 100)
' Define the procedure Sub ShowRandomBetween(min As Integer, max As Integer) dim n As Integer n = (Rnd() * (max - min)) + min MsgBox(n) End Sub ' Call the procedure ShowRandomBetween(10, 20) ShowRandomBetween(50, 100)
import random # define the procedure def show_random_between(min, max): print(random.randint(min, max)) # call the procedure show_random_between(10, 20) show_random_between(50, 100)
// define the procedure prcedure show_random_between(min, max): print(random(min, max)) endprocedure // call the procedure show_random_between(10, 20) show_random_between(50, 100)
{ not specified in eduqas pseudocode reference }
// define the procedure void showRandomBetween(int min, int max) { Random r = new Random(); int number = r.Next(min, max); Console.WriteLine(number); } // call the procedure showRandomBetween(10, 20); showRandomBetween(50, 100);