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

Everett Yates
Everett Yates
9,280 Points
Posted by Everett Yates
Everett Yates
9,280 Points

Why doesn't the reverse_evens function work?

I did this problem in IDLE and my function works just like in the example he gave.

slices.py 
def first_4(whatever):
    return whatever[:4]
def first_and_last_4(something):
    return something[:4] + something [-4::1]
def odds(item):
    return item[1::2]
def reverse_evens(item):
    return item[::-2]

1 Answer

james south
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
james south
Front End Web Development Techdegree Graduate 33,271 Points
james south
.a{fill-rule:evenodd;}techdegree seal-36
james south
Front End Web Development Techdegree Graduate 33,271 Points

add another element to your test case and see if you still get the right elements. you are slicing every other element, not necessarily the even indices. if the last element has an odd index, you will get only the odd indices. to fix you can slice evens first, then reverse, or you can test for length and remove the last element if needed then slice every other element from the end like you are.