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While loops
Lesson 16 of 77
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PYTHON BASICSChapter 3 · Loops and iteration

Looping while true

A while loop keeps running as long as a condition remains True. You must make sure the condition eventually becomes False, or your loop will run forever (an infinite loop).

Worked example

How it reads

  • while stars > 0: checks the condition before each turn
  • stars = stars - 1 decreases the counter so the loop eventually stops
Cloud tip: Always modify the variable in your condition inside the loop body, otherwise you will get stuck in an infinite loop.
main.py
PYTHON
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Console
Run your code to see its output here.
YOUR TURN

Start with n = 1 and use a while loop to keep doubling it while it is 100 or less. Print the result: 128.

Press Run to check your work.
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