11.2: Pseudocode Examples for Control Structures
- Page ID
- 10304
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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