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Python Python Collections (2016, retired 2019) Slices Slice Functions

Rahul Dharamdasani
Rahul Dharamdasani
1,597 Points
Posted by Rahul Dharamdasani
Rahul Dharamdasani
1,597 Points

The reverse_evens function seems to be incorrect. Can someone point out the error ?

The reverse_evens function that I have typed out seems correct to my knowledge. I even tried to run in on pycharm and it works perfectly. But I get the error: Didn't get the desired value for reverse_evens. Am I wrong somehow ?

slices.py 
def first_4(num):
    newlist = list(num)
    return newlist[0:4]

def first_and_last_4(num1):
    newlist = list(num1)
    f4 = newlist[0:4]
    l4 = newlist[-4:]
    return f4+l4

def odds(num3):
    newlist = list(num3)
    return newlist[1::2]

def reverse_evens(num):
    alist = list(num)
    return alist[-1::-2]

1 Answer

Alex Koumparos
seal-mask
.a{fill-rule:evenodd;}techdegree
Alex Koumparos
Python Development Techdegree Student 36,887 Points
Alex Koumparos
.a{fill-rule:evenodd;}techdegree
Alex Koumparos
Python Development Techdegree Student 36,887 Points

Hi Rahul,

Try your code with inputs of both even length and odd length.

This challenge can't be completed with a single slice. Think about how you could solve it by getting halfway to the solution with a single slice, then performing another slice on that result to finish it off.

Cheers

Alex