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Python Introducing Lists Build an Application The Application

Posted by Timothy Tseng
Timothy Tseng
3,292 Points

Validating user inputs

def prompt_user():
    option = input("Please select an option, to view options type in 'HELP' ")
    if option != '1' or '2' or 'DONE' or 'HELP':
        print("Invalid option, type HELP for valid commands. ")

How come in the above code when I type in DONE or HELP in the command my program is saying it's invalid? I also tried without the single quotes. I'm guessing it's because I have both string and ints in the same line?

1 Answer

jhon white
jhon white
20,006 Points

Your code has two things wrong : 1- You should use (and) not (or) . 2- The condition should be used for every statement . here is: def prompt_user(): option = input("Please select an option, to view options type in 'HELP' ") if option != '1' and option !='2' and option !='DONE' and option !='HELP': print("Invalid option, type HELP for valid commands. ")

prompt_user()

ps: your numbers('1','2') are strings too. Good luck!!