Question

I have 5 different strings i am searching for in a text file. I am trying to get python to ask the user for a “room number” and if any of those numbers match, to continue, otherwise ask again until a correct number is entered.

I can get it to work if try:

roomNumber = input("Enter the room number: ")
while roomNumber != ("L1"):
    roomNumber = input ("Please enter a correct room number:")

However i wish to have a positive match for L1, L2, L3, L4, and L5.

I tried:

roomNumber = input("Enter the room number: ")
while roomNumber != ("L1", "L2", "L3", "L4", "L5"):
    roomNumber = input ("Please enter a correct room number:")

however this doesn’t work and i assume it wants all of those matches, not just the one.
I also tried putting each value in a ([ ]) and also tried using OR between each value but didn’t work either.

I’ve been searching for ages and can’t seem to find examples of multiple matches in a while loop.

Surely i’m missing something simple?

Answer 1

Python has an in/not in operator that is useful for things like this:

while roomNumber not in ("L1", "L2", "L3", "L4", "L5"):
    ...

It works for almost any container type in Python; all of the following are true:

1 in [1, 2, 3]
3 in range(50)
"foo" in { "foo": "bar" }
"bar" not in { "foo": "bar" } # (it only looks at keys for dictionaries)