While loop breaks despite conditions being false

Question

The code asks user to pick letter a, b, or c.

while True:
    user_input1 = input("Please choose a, b , c: ")
    if user_input1 == "a" or "b" or "c":
        break
print("This should be printed when user types in a, b, or c.")

The problem comes in when I don't type a, b , or c the loop breaks and prints the statement anyway. If I type in number 2 for an example, the code executes the break and prints the statement which isn't suppose to cause it's not letter a, b , or c.

I tried put the input variable outside the while loop but it still happens.

Your condition needs to be changed to `if user_input1 == "a" or user_input1 == "b" or user_input1 == "c"`. Although there is a better way to implement this logic using lists and the `in` keyword. — Gabe Morris, Jan 26 '22 at 00:35
you're doing ` if user_input1 == "a" or "b" or "c":` where "b" is considered as true, and "c" too. you need to do: ` if (user_input1 == "a") or (user_input1 == "b") or (user_input1 == "c"):` or better: `if user_input1 in ["a","b","c"]:` — Ulises Bussi, Jan 26 '22 at 00:36
Does this answer your question? [How to test multiple variables for equality against a single value?](https://stackoverflow.com/questions/15112125/how-to-test-multiple-variables-for-equality-against-a-single-value) oe https://stackoverflow.com/questions/3260057/how-to-check-variable-against-2-possible-values/3260070 — JonSG, Jan 26 '22 at 00:44
This is probably the most commonly asked python question. You all with 5 figure reps know this is a duplicate and should not be answering. — JonSG, Jan 26 '22 at 00:45
Yes adding parenthesis () in the if statement fixed it. It worked when it went from user_input1 == "a" or "b" or "c": to user_input1 == ("a" or "b" or "c"): . Why does adding parenthesis fix it? — iriandurian, Jan 26 '22 at 01:02
I don't think it would actually fix it. It will only work for "a" — Sash Sinha, Jan 26 '22 at 01:24

score 2 · Answer 1 · answered Jan 26 '22 at 00:40

2

while True:
    user_input1 = input("Please choose a, b , c: ")
    if user_input1 in [ "a" , "b" ,"c"]:
        break
print("This should be printed when user types in a, b, or c.")

answered Jan 26 '22 at 00:40

M. Twarog

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score 0 · Answer 2 · answered Jan 26 '22 at 00:37

you are condition is wrong or 'b' is not comparing input with it , so 'b' is always true or 'c' , you need to change it to :

while True:
    user_input1 = input("Please choose a, b , c: ")
    print(user_input1)
    if user_input1  in ["a","b","c"]:
        break
print("This should be printed when user types in a, b, or c.")

While loop breaks despite conditions being false

2 Answers2