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Python Python Basics (2015) Letter Game App Even or Odd Loop

Name:GoogleSearch orJonathan Sum
Name:GoogleSearch orJonathan Sum
5,039 Points
Posted by Name:GoogleSearch orJonathan Sum
Name:GoogleSearch orJonathan Sum
5,039 Points

def even_odd(num): # If % 2 is 0, the number is even. # Since 0 is falsey, we have to invert it with not.

return not num % 2 why there is a reutrn not here?

even.py 
def even_odd(num):
    # If % 2 is 0, the number is even.
    # Since 0 is falsey, we have to invert it with not.
    return not num % 2

2 Answers

Quentin Durantay
Quentin Durantay
17,880 Points
Quentin Durantay
Quentin Durantay
17,880 Points

No, you have several values which are falsey by default for each programming languages, and other that are truthy. In all programming languages, 0 (the number zero) is always falsey. But in the precise case of this function even_odd you want the result 0 to give you back True, so you have to negate False to get back True.

Quentin Durantay
Quentin Durantay
17,880 Points
Quentin Durantay
Quentin Durantay
17,880 Points

You want the function to give you back True when the number is even, that is the number % 2 = 0. The thing is, 0 is falsey in Python (like in all other languages), so you have to put not, so that when the result is 0, the function inverts False and give you True (because not False = True).