无法弄清楚条件

Question

I'm working on a 30 day of code challenge and passed 5/8 tests on my code and can't figure out the reason it keeps failing

The parameters are that if N is odd print weird, if N is even and in the range of 2-5 print not weird if N is even and in the range of 6-20 print weird if N is even and greater than 20 print not weird

N = int(input())

if  N % 2 == 0 and range(2-5): 
    print("Not Weird")
elif N % 2 == 0 and range(6-20): 
    print("Weird")
elif N % 2 == 0 and N > 20:
    print("Not Weird")
elif N % 2 == 1 :
    print("Weird")

Answer 1

if  N % 2 == 0 and range(2-5): 

does not do what you think, it should instead be something like:

if  N % 2 == 0 and N in range(2, 6): 

Specifically:

• each sub-condition (on either side of your 'and') should be complete.
• range, in your example, was range(-3) since that's what 2-5 gives.
• the range is half open, meaning it includes the start but excludes the end.

Answer 2

1) The function range with defined begging and end is a function that takes 2 parameters as argument. Therefore I'd recommend you to use it as range(x,y) instead of range(xy) .

If you use it like range(2-5) , you're actually asking for range(-3) . When used with only 1 arg, the function range will give you a list of int from 0 up to the input arg .

Regarded that there is no integer greater than 0 and less than -3 , then you're getting an empty list.

2) Also, notice that the upper limit is not inclusive:

>>> for i in range(2,5):
...     print(i)
... 
2
3
4

so you might consider to use range(2,6) for the first case, range(6,21) for the second case and so on and so forth..

Answer 3

To expand on @paxdiablo's answer, you can also use the step argument of range to test for even numbers:

if N in range(2, 6, 2):