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

Posted by Mark Chesney
Mark Chesney
11,747 Points

reverse_evens in slice-functions: Does anyone know why I'm stuck?

Does anyone know why I'm stuck? This is Challenge Task 4 of 4

If I do this, it works just fine in the console:

x=[1,2,3,4,5] x[::-2] x[-1::-2] # This returns an equivalent answer [5,3,1] # Example answer

Though the question is asking for reverse_evens, it's asking for elements in the even-numbered indices (which happen to be odd numbers in the example). I say this because I was wondering if my interpretation of the question is incorrect -- or is the example incorrect?

Thanks!

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

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

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

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

1 Answer

Viraj Deshaval
Viraj Deshaval
4,874 Points
Viraj Deshaval
Viraj Deshaval
4,874 Points

You are super close to the solution. Your solution works in some cases and do not work in other cases. For example if iterable = [1,2,3,4,5,6]. Idea here is to first take the even indexes and then reverse them. Hope this helps!

Mark Chesney
Mark Chesney
11,747 Points

Wow, thank you very much Viraj! :)