Question

I have a program to quiz me on how far planets are from the sun. The only problem is, no matter what answer I put it always shows up as correct. Here is a link to my code: http://pastebin.com/MimECyjm

If possible, I would like a more simplistic answer because I am not that proficient in python yet

Code in question:

mercury = "57.9"
mercury2 = "57900000"

def Mercury():
    ans = raw_input("How far is Mercury from the sun? ")
    if mercury or mercury2 in ans:
        print "Correct!"
        time.sleep(.5)
        os.system("cls")
        main()
    else:
        print "Incorrect!"
        Mercury()

Answer 1

The problem is that you have:

if mercury or mercury2 in ans:

This if statement will be True if mercury evaluates to True (which it always does) or when mercury2 in ans is True.

mercury is a non-empty string (mercury = "57.9") which will evaluate to True. For example, try bool("57.9") to see that Python always computes True for non-empty strings. If the string is empty then it will be False.

So no matter what the user answers, your code will always say that it is correct. Here’s what you could write:

if mercury in ans or mercury2 in ans:

but it’s probably better to write (see discussion in comments below):

if ans in [mercury, mercury2]: