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

Erik Luo
Erik Luo
3,810 Points
Posted by Erik Luo
Erik Luo
3,810 Points

What does "decrement start by 1" mean?

What does "decrement start by 1" mean?

even.py 
import random
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
start = 5
while start True:
    ran = random.randint(1, 99)
    if even_odd(ran) = 0:
        print("{} is even".format(ran))
    elif even_odd(ran) != 0:
        print("{} is odd".format(ran))
    start - 1

2 Answers

Zach Hudson
Zach Hudson
7,702 Points
Zach Hudson
Zach Hudson
7,702 Points

Erik,

I changed a couple things in your code and verified that is does pass the challenge. See my changes below:

  • I changed the while loop line to include an "is"
  • The function even_odd(num) returns a 0 (zero) if a number is NOT odd, so your if and elif statements are backwards
  • To decrement start by 1, you needed to add an "=" sign after the minus in order to subtract properly

See the code below (with the changes implemented):

import random
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
start = 5
while start is True:
    ran = random.randint(1, 99)
    if even_odd(ran) != 0:
        print("{} is even".format(ran))
    elif even_odd(ran) == 0:
        print("{} is odd".format(ran))
    start -= 1
Zach Hudson
Zach Hudson
7,702 Points
Zach Hudson
Zach Hudson
7,702 Points

Based on your code, start = 5, which means you are supposed to be looping through 5 times. Each time you loop through you are supposed to decrement start by 1, or subtract 1 from start, until start = 0 and the loop stops.

Instead of..

start - 1

You should have...

start -= 1

The above code is equivalent to start = start - 1.

Erik Luo
Erik Luo
3,810 Points
Erik Luo
Erik Luo
3,810 Points

I did that, still doesn't work