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Python

Posted by Servicios Adquiridos SA de CV
Servicios Adquiridos SA de CV
886 Points

Reverse evens exercise is driving me crazy!

          def first_4(something):
    return something[0:4]
def first_and_last_4(something):
    return something[:4] + something[-4:]
def odds(something):
    return something[1::2]

def reverse_evens(something):
    if something[0]%2 =0:
        evens = something[::3]
        return evens [::-1]
    else:
        odds= something[::2]
        return odds [::-1]

The last function is causing me troubles, I have to return a evens list backwards, but I don't know why is not working.

2 Answers

<noob />
<noob />
17,063 Points

Hello, I remember this function, it was hard. however after reviewing some solutions ppl mentioned that u also need the numbers to be evens the solution is:

def reverse_evens(something):
    return something[::2][::-1]

First,we want to step 2 indexes each time, so for example if we start at index zero, we step to index 2 and thats how we always in a even index. Second, we now want to reverse the output so we simply use the [::-1]

hope un understand ;]

Servicios Adquiridos SA de CV
Servicios Adquiridos SA de CV
886 Points
Servicios Adquiridos SA de CV
Servicios Adquiridos SA de CV
886 Points

So helpful! Thanks a lot