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

Kyle Petran
Kyle Petran
5,017 Points
Posted by Kyle Petran
Kyle Petran
5,017 Points

Fairly certain my answer gives the proper return

why isn't reverse_evens ( ) working?

slices.py 
def first_4(itera):
    return itera[:4]
def first_and_last_4(itera):
    return itera[:4]+itera[-4:]
def odds(itera):
    return itera[1::2]
def reverse_evens(itera):
    return itera[len(itera)-1::-2]

1 Answer

Steven Parker
Steven Parker
231,007 Points
Steven Parker
Steven Parker
231,007 Points

It might work for some test cases. But to work in all cases it needs one of two possible strategies:

  • compute the starting position based on the length of the array, or
  • extract the even indexes first, and then reverse them in a separate operation