[Tutor] optional else with while

[Alan Gauld]

On 11/10/2020 18:07, Manprit Singh wrote:

> to understand how an optional else clause works with  while loop  .
> 
> n = int(input("Enter any number"))
> initial = n//2
> while initial > 1:
>     if n % initial == 0:
>         print("Greatest factor of",n,"is",initial)
>         break
>     initial -= 1
> else:
>     print("It is a prime number")


I'd say that's a pretty fair demonstration of a while/else.
Mostly you don't need it since the code will just continue
after the loop, but in cases like this where you want to
do something only if the while exits "normally" (ie no breaks)
the else clause is the right choice.

-- 
Alan G
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