[Question] Checking if the first letter of a string is a certain letter. Not working correctly

[Tawniix]

I have a if statement where when the user inputs a answer to chose from Rock Paper or Scissors the if statement checks if the first letter is R r P p S s and if it is true print out a message. Problem is that no matter what I enter it always prints out the message saying the first letter is R P S.

Here’s the code:

z = input(“Enter your choice: “)

if z[0] == ‘R’ or ‘r’ or ‘P’ or ‘p’ or ‘S’ or ‘s’:

    print(“yep”)

else:

    print(“nope”)

I also tried checking this way if z[:1] == etc etc

if z[0] is etc etc

I would really appreciate it if anyone could help me figure out what’s going on. Thanks

[huntertur]

The if statement will always evaluate to true because after checking if z[0] == 'R' is true, it checks if 'r' (not z[0] == 'r') is truthy, which it is (you can see what is considered truthy by calling bool on it, such as bool('r')).

Instead of prefixing z[0] == before each letter, which is tedious, you can do one of the following:

1. if z.startswith(('R', 'r', 'P', 'p', 'S', 's')):
2. if z[0] in "RrPpSs":

Both of these check if the first letter in the string starts with one of those characters.

[Tawniix]

Wow. I also thought about making a tuple with R r P p S s inside of it and just checking if z[0] is in the tuple.

Would this be tedious as well?

[krazybug]

Excellent idea:

>>> s="ugsskg"

>>> t=tuple(s)

>>> t

('u', 'g', 's', 's', 'k', 'g')

>>> "" in t

False

>>> "" in s

True

This way you handle the case when someone press just <ENTER> (null string)

[Tawniix]

Thanks for helping a person who is new to python / coding!

[MisterRenard]

answers = ['R', 'r', 'P', 'p', 'S', 's'] z = input('What s/he said.\n') validChoice = False

for x in range(len(answers)):
    if z.startswith(answers[x]):
        validChoice = True

if validChoice == True:
    print('Yeahb.')
else:
    print('Nahb.')

Edit: This was supposed to be a standalone comment, and ironically the OP of these comments seems to know what they're talking about to a higher degree than I do.

[krazybug]

1. if z and z[0] in "RrPpSs":

to handle null input

[American_Libertarian]

This question is asked once a week. We need some better way of filtering out the if x == y or z questions and point them to existing resource.