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

Posted by Harold Nelson
Harold Nelson
6,915 Points

Possible bug in Python Collections Challenge task 4 of 4

Here is the code I submitted with a test based on the problem specification. It appears to be working correctly, but is not accepted.

def reverse_evens(it): rev = it[::-1] eve = rev[0::2] return(eve) l = [1, 2, 3, 4, 5] reverse_evens(l) [5, 3, 1]

slices.py 
def first_4(it):
    slice = it[:4]
    return(slice)
def first_and_last_4(it):
    slice1 = it[:4]
    slice2 = it[-4:]
    return(slice1 + slice2)
def odds(it):
    sliceo = it[1::2]
    return(sliceo)
def reverse_evens(it):
    rev = it[::-1]
    eve = rev[0::2]
    return(eve)
Venkat SOMALARAJU
Venkat SOMALARAJU
2,448 Points
Venkat SOMALARAJU
Venkat SOMALARAJU
2,448 Points

True, tried for 72 hours with this code, couldn't avoid "Bummer!" :)

followed below answer, and it works. Don't understand what's wrong with our approach.

1 Answer

reanimator313
reanimator313
6,005 Points
reanimator313
reanimator313
6,005 Points 
def reverse_evens(it):
    eve = it[::2] # remove the odd index
    rev = eve[::-1] # reverse the even index
    return(rev)
Harold Nelson
Harold Nelson
6,915 Points

Thanks, reversing the two steps did the trick.