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

Posted by Mathew Yangang
Mathew Yangang
4,433 Points

returning item with even index

I keep having errors returning every item with even index

slices.py 
def first_4(item):
    return item[:4]
def first_and_last_4(things):
    firstFour = things[:4]
    lastFour = things[-4:]
    sum = firstFour + lastFour 
    return sum
def odds(item):
    return item[1::2]
def reverse_evens(item):
    evenNumbers = item[::-]
    return evenNumbers[::2]

1 Answer

Grigorij Schleifer
Grigorij Schleifer
10,365 Points
Grigorij Schleifer
Grigorij Schleifer
10,365 Points

Hi Mathew,

your logic is correct as far I can see. You only need to tweak the last method a little bit. :sunglasses:

I would suggest:

  • store every second member of item beginning from 0 in evenNumbers using a appropriate step ...
  • return a reversed version of evenNumbers using -1 step (hint)

Try it on your own and let us know if you want to see a code snippet.