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

Thananjaya Chakravarthy
Thananjaya Chakravarthy
4,672 Points

how to return in reverse order of even index?

I have carried out same codes in the workspace. I got the output.

but.. why am not getting during practice session..?

slices.py
def first_4(name):
    hi=name[0:4]
    return hi

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

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

def reverse_evens(s):
    if len(s)%2 == 0: 
        return s[-1::-2]
    else:
        return s[-2::-2]

2 Answers

Kenneth Love
STAFF
Kenneth Love
Treehouse Guest Teacher

All ordered/indexed iterables can be sliced (you can't slice dicts or sets as they don't have an order/index).

Slices are, themselves, ordered and indexed.

How would you get all of the items with an even index? How would you reverse an iterable with a slice?

Hi Thananjaya,

An even length iterable would end on an odd index. Make sure that you're starting on the correct item from the end.