In Python, is it possible to make a while loop that will occur if an input is equal to different values?

Question

In Python, I am writing a program that allows the user to encrypt messages that they input. There are two methods of encryption that they can select, and I am trying to create a while loop that will trigger if the user chooses an option that is not equal to the two options, 1 and 2.

option1 = input('Which encryption method would you like to use? 1 = Across (NOPQ ...) and 2 = Backwards (ZYXW ...)')
while option1 != [1, 2]:
    print 'Please type 1 or 2.'
    option1 = input()

If I write this, than I will be asked to input 1 or 2 no matter what I type.

use `not in` instead of `!=`. Remember, you want to test if `option1` _**is in_** `[1, 2]` not if `option1` **_is_** `[1, 2]`. — Christian Dean, Nov 18 '17 at 20:46
and convert input to integer as well. Well in python 2 that'll work, but will break in python 3. — Jean-François Fabre, Nov 18 '17 at 20:46
@Jean-FrançoisFabre Or just make `1` and `2` strings. Either way would work. — Christian Dean, Nov 18 '17 at 20:47
see also: https://stackoverflow.com/questions/15112125/how-do-i-test-one-variable-against-multiple-values — Jean-François Fabre, Nov 18 '17 at 20:49

score 1 · Accepted Answer · edited Nov 18 '17 at 20:49

1

Replace != with not in like in the example below:

option1 = int(input('Which encryption method would you like to use? 1 = Across (NOPQ ...) and 2 = Backwards (ZYXW ...)'))
while option1 not in [1, 2]:
    print 'Please type 1 or 2.'
    option1 = int(input())

edited Nov 18 '17 at 20:49

Christian Dean

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answered Nov 18 '17 at 20:49

zeeks

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score 0 · Answer 2 · answered Nov 18 '17 at 20:52

0

Basically, you need to :

option1 = int(raw_input())

then as you want to see if it's in a list

while option1 not in [1,2]:
    print 'Please type 1 or 2.'

` option1 = int(input())

answered Nov 18 '17 at 20:52

kmcodes

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In Python, is it possible to make a while loop that will occur if an input is equal to different values?

2 Answers2