6.9: while Loops vs. for Loops — Read

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A common beginner question is: How do I know whether to use a while loop or a for loop?

Question	Recommended Loop
Do I know exactly how many times the loop should run?	Use a for loop.
Am I looping through all elements of an array?	Usually use a for loop.
Am I asking the user for input until the input is valid?	Usually use a while loop.
Am I repeating until some condition changes?	Use a while loop.
Am I searching until I find something?	Either can work; a for loop with break is common.

Use for when you know the number of repetitions. Use while when you know the condition for stopping.

This page titled 6.9: while Loops vs. for Loops was last modified on Tue, 30 Jun 2026 02:11:42 GMT and is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Zara Noroozi.

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