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Computer ScienceClass 11 (CBSE) Resolved

Why does my Python while loop run forever and never stop?

I wrote a while loop to print numbers but it just keeps printing and my screen freezes. I have to force-close the program. What am I doing wrong?

Asked by Ananya Sharma 50 45d ago
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1 answer

Accepted answer
8

An infinite loop almost always means the loop condition never becomes False because you forgot to update the variable inside the loop. For example, 'i = 1; while i <= 5: print(i)' runs forever because i stays 1. You must change the control variable each iteration: add 'i = i + 1' (or 'i += 1') as the last line inside the loop. Now i grows to 6, the condition i <= 5 becomes False, and the loop stops. Always check three things: the variable is initialised before the loop, the condition will eventually be False, and the variable is updated inside the loop. If any one is missing, the loop runs forever.

D
Deepak Kulkarni
355 pts· 45d ago

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