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

Posted by blckphoenix8
blckphoenix8
2,946 Points

Even Odd Loop Code

The code I wrote for this exercise runs properly in workspace but the exercise says I'm wrong and can't continue. What is it looking for that isn't in my code? Thanks.

even.py 
import random
start = 5

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

while start != 0:
    num = random.randint(1, 99)
    if even_odd(num):
        print("{} is even.".format(num))
    else:
        print("{} is odd.".format(num))
    start -= 1

3 Answers

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

The checker doesn't like the period at the end of the print strings. 

print("{} is even".format(num))
print("{} is odd".format(num))
Byron Rodriguez
Byron Rodriguez
Courses Plus Student 3,771 Points
Byron Rodriguez
Byron Rodriguez
Courses Plus Student 3,771 Points

I keep getting "Bummer Try again!". I copied and pasted the code above which was the same as the code I wrote but still getting the error. This is frustrating!

Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

My print statements are meant to replace your print statements. Here is the full code:

import random
start = 5

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

while start != 0:
    num = random.randint(1, 99)
    if even_odd(num):
        print("{} is even".format(num))  # <-- sentence period removed
    else:
        print("{} is odd".format(num))  # <-- sentence period removed
    start -= 1
Byron Rodriguez
PLUS
Byron Rodriguez
Courses Plus Student 3,771 Points
Byron Rodriguez
Byron Rodriguez
Courses Plus Student 3,771 Points

Thank you for your response Chris. I see what I was doing wrong. I was checking if "even_odd(num) != 0". I didn't realize that the function would return True or False.

Evan Waterfield
Evan Waterfield
3,240 Points
Evan Waterfield
Evan Waterfield
3,240 Points

Can someone explain the start aspect and return not num % 2? I know that's vague but I'm having a hard time with these challenges. I understand the num statement, the if, and else.

Quinton Gordon
Quinton Gordon
10,985 Points
Quinton Gordon
Quinton Gordon
10,985 Points

Hey Evan,

The start variable is being using the count the number of loops. So for every completed loop the value is start is being decreased by 1 and when the value is 0 the loop will stop due to start no longer being "truthy".

The return statement is also a matter of truth logic. So the function checks to see if a number is even by dividing it by 2. Any even number divided by 2 leaves a remainder of 0. The problem the 'not' is solving is that 0 is a "falsey" statement. So without the not the function would be responding that the number is not an even when it is. So we inverse the response.