Write pseudocode statements for: the declaration of variables

11.1 Programming Basics

Objective

Write pseudocode statements for the declaration of variables.

Why Declare \cdot ariables?

In pseudocode a variable must be declared before it is used so that the computer knows:

• The identifier (name) of the variable.
• What type of data it can store (e.g., integer, real, Boolean).
• Optionally, an initial value.

Common Data Types

• Integer – whole numbers, e.g., \$-3\$, \$0\$, \$42\$.
• Real – numbers with a fractional part, e.g., \$3.14\$, \$-0.001\$.
• Boolean – logical values TRUE or FALSE.
• Character – a single symbol, e.g., 'A', '9'.
• String – a sequence of characters, e.g., "Hello".

Pseudocode Syntax for Declaration

The generic form is:

DECLARE <identifier> : <type> [← <initial‑value>]

Square brackets indicate that the initialisation part is optional.

Examples of \cdot ariable Declarations

Step‑by‑Step Procedure for Declaring \cdot ariables

1. Identify the purpose of each variable.
2. Choose an appropriate data type.
3. Write the DECLARE statement using the syntax above.
4. If a sensible starting value exists, include it after the arrow (←).
5. Place all declarations at the beginning of the algorithm or in a dedicated section.

Common Pitfalls

• Omitting the type – the compiler cannot infer the type in strict pseudocode.
• Using a name that conflicts with a reserved word (e.g., IF, WHILE).
• Assigning an initial value that does not match the declared type.