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

Slices question

Can't figure this one out. Again, it works in workspaces and I think I've built on each of the previous tasks correctly.

slices.py
def first_4(passed):

    return passed[:4]

def first_and_last_4(passed):

    return passed[:4] + passed[-4:]

def odds(passed):

    temp = passed[1:]
    return temp[::2]

def reverse_evens(passed):

    return passed[-1::-2]

1 Answer

Steven Parker
Steven Parker
231,248 Points

The final function will work for some inputs. On others it will return "reverse_odds" instead. It depends on how many items are in the list.

To always return reverse evens, there's two basic strategies:

  • compute the starting position based on the list size
  • extract the even index values first, then reverse them

Either one will pass the challenge when implemented correctly.