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Python

Posted by Bernt Jensen
Bernt Jensen
840 Points

while

name=input('whats your name? ') answer=input(f'{name} do you understand while loops? ') while answer!='Yes' or 'yes': print('while loops blablabla') input('and now? ') else: print('good for you')

why does it print 'while loops blablabla' when i type yes?

2 Answers

Steven Parker
Steven Parker
243,656 Points
Steven Parker
Steven Parker
243,656 Points

The logical operator "or" should be used with complete comparison expressions. A non-empty string is "truthy" by itself, so adding "or "yes"" to any comparison will make the whole expression always True.

Plus, combining two inequalities will also always be "True", since one or the other will always not match. So you probably want to combine those tests using "and" instead:

while answer!='Yes' and answer!='yes':

And you can make it a bit more compact by using case conversion and just one comparison:

while answer.lower() != 'yes':
Bernt Jensen
Bernt Jensen
840 Points
Bernt Jensen
Bernt Jensen
840 Points

thanks :)