# 11.2: Pseudocode Examples for Control Structures

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## Overview

No standard for pseudocode syntax exists. However, there are some commonly followed conventions to help make pseudocode written by one programmer easily understood by another programmer. Most of these conventions follow two concepts:

• Use indentation to show the action part of a control structure
• Use an ending phrase word to end a control structure

The sequence control structure simply lists the lines of pseudocode. The concern is not with the sequence category but with selection and two of the iteration control structures. The following are commonly used ending phrase-words:

 Control Structure Ending Phrase Word If then Else Endif Case Endcase While Endwhile For Endfor

The Do While and Repeat Until iteration control structures don't need an ending phrase-word. We simply use the first word, then the action part, followed by the second word with the test expression. Here are some examples:

## Selection Control Structures

Pseudocode: If then Else
If age > 17
Display a message indicating you can vote.
Else
Display a message indicating you can't vote.
Endif

Pseudocode: Case
Case of age
0 to 17   Display "You can't vote."
18 to 64  Display "You're in your working years."
65 +      Display "You should be retired."
Endcase


## Iteration (Repetition) Control Structures

Pseudocode: While
count assigned zero
While count < 5
Display "I love computers!"
Increment count
Endwhile

Pseudocode: For
For x starts at 0, x < 5, increment x
Display "Are we having fun?"
Endfor

Pseudocode: Do While
count assigned five
Do
Display "Blast off is soon!"
Decrement count
While count > zero

Pseudocode: Repeat Until
count assigned five
Repeat
Display "Blast off is soon!"
Decrement count
Until count < one


This page titled 11.2: Pseudocode Examples for Control Structures is shared under a CC BY license and was authored, remixed, and/or curated by Kenneth Leroy Busbee (OpenStax CNX) .