You haven't called the function!

def test(foundN):
    if foundN%2 == 0:
        print "The number ", foundN, "is ok."
    else:
        print "Try another number. "

foundN = input("Enter number: ")
test(foundN)

This is very similar to another answer, but, let's consider modulus 3 for simplicity. Modulus 3 transforms this 0 1 2 3 4 5 6 7 8 9 ... into this 0 1 2 0 1 2 0 1 2 0 ... Now, how would you extend that into negative numbers? I would do it like so: ... -4 -3 -2 -1 0 1 2 3 4 ... ... 2 0 1 2 0 1 2 0 1 ... (the 0 1 2 cycle is preserved) This is the same that happens with % 8: ... -6 -5 -4 -3 -2 -1 0 1 2 3 ... Becomes ... 2 3 4 5 6 7 0 1 2 3 ... Cheers! Edit: clarify the cycle

you are looking for the modulo operator:

a % b

for example:

>>> 26 % 7
5

Of course, maybe they wanted you to implement it yourself, which wouldn't be too difficult either.

Well, first of all, you need to perform the test to see if the user has input 0 for the divisor (the number to divide by) before you attempt the division. Otherwise, you'll hit an error. Fortunately, you can do this by simply rearranging your code. Also, you're defining your dividend and divisor within your function; you don't need to send them as parameters to the function. This, for example, ought to work (note the lack of a def header): num_1 = int(input("Please enter the number to divide by: ")) num_2 = int(input("Please enter the number to divide: ")) if num_1 == 0: print('ERROR! Division by zero is undefined.') elif num_2 == 0: print('Zero divided by anything is zero.') else: remainder = num_2 % num_1 if remainder: print(f"{num_2} is not divisible by {num_1}, there is a remainder of {remainder}.") else: print(f"{num_2} is divisible by {num_1}") NOTE: Edited to address spelling error.

Hi there! I'm just going to expand a little on what James has already said. I know the "modulo/modulus" operator can be confusing for some, so let's not use it when we're reading it out loud. You could read it this way: "If the number divided by 2 has a remainder of 0 then do this, otherwise do this". And let's take a look at some examples: 1 % 2 will result in a 1. One divided by two results in 0 with a remainder of 1. 2 % 2 will result in a 0. Two divided by two results in a 1 with a remainder of 0. 3 % 2 will result in a 1. Three divided by two results in a 1 with a remainder of 1 4 % 2 will result in a 0. Four divided by two results in a 2 with a remainder of 0. 5 % 2 will result on a 1. Five divided by two results in a 2 with a remainder of 1. Seeing a pattern here? :smiley: Whenever you see if( x % y == 0), you can read that also as "If x is evenly divisible (no remainder) by y". We say a number is evenly divisible by another when it can be divided by that number without a remainder. An odd number is any number that is not evenly divisible by 2. An even number is any number that is evenly divisible by 2. Hope this helps! :sparkles:

You can do 5//2 and get 2 instead of the 2.5 you'd get with 5/2.

As long as you're in Python 3 , you can also use floor(5/2).

Both ways of doing it give you the floor-rounded answer.