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

Reverse evens question, why does this work in sublime but not here?

In sublime if I input the same info I get this as the answer [5, 3, 1] so why doesn't my solution pass?

def first_4(items):
    return items[:4]

def first_and_last_4(items):
    return items[:4] + items[-4:]

def odds(items):
    return items[1::2]

def reverse_evens(items):
    return items[::-2]

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,404 Points

Keep in mind that the length of the list to reverse may have an even or odd number of items. A simple reversal of every other item is not sufficient.

Hint: try grabbing the even indexed items first, then reversing that list in a second slice.

Post back if you need more help. Good luck!!!

I eventually passed with this:

def reverse_evens(items):
    if len(items) %2!=0:
        return items[-1::-2]
        return items[-2::-2]
Chris Freeman
Chris Freeman
Treehouse Moderator 68,404 Points

You can also use two slices with no if

return items[::2][::-1]