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

Vianney Gall
Vianney Gall
5,342 Points

I don't get it right on the challenge but it works on my workspace. How come?

For the part 4 of this challenge, my code does not work, but when I write this on my workspace, it works...

On my workspace it looks like this:

def reverse_evens(iterable): return iterable[::-2] print(reverse_evens(input("What is your iterable: ")))

slices.py
def first_4(iterable):
    return iterable[0:4]


def first_and_last_4(iterable):
    one = iterable[0:4]
    two = iterable[-4:]
    return one + two

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

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

2 Answers

Steven Parker
Steven Parker
229,744 Points

This method will work for some data, based on the length of the list. But to make it work for all data, you'll need one of these two strategies:

  • set the starting position based on the length (even or odd) of the list
  • take the even indexed items first, then reverse them as a separate operation

Either method will work when correctly implemented, but the second one is a bit easier to do.

Vianney Gall
Vianney Gall
5,342 Points

Excellent! Thank you so much!!!