C++ Fundamentals · Loops · Lesson 11 of 24
while and do-while Loops
Concept
while and do-while Loops
while checks its condition before each iteration. do-while runs the body at least once before checking.
By the end of this lesson
- Explain the core idea behind while and do-while Loops.
- Predict output before running a change.
- Test one realistic and one unusual input.
- Use the result to make the next decision.
How to study this page
- 1. Read one concept.
- 2. Change the example.
- 3. Run, compare, and explain.
- 4. Complete the challenge below.
Self-check before continuing
Without looking at the example, describe what changes when you modify one input in while and do-while Loops. Then reopen the editor and prove your explanation with a small test.
You are ready to continue when you can predict, test, and explain the result.
Your turn
Write a do-while loop that runs exactly once even if the condition starts false.
Need a nudge?
Ask about this lesson or your next move. The guide explains the path without taking the work away from you.
Ready for the next lesson?
Mark this lesson complete when you have finished the exercise.
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