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

Posted by jeffreywilliam
jeffreywilliam
10,432 Points

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

I am not very clear on this challenge. I have the above function which returns the values outlined in the description of the challenge. I am not sure of what I am missing. Above is my function definition.

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


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

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

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

2 Answers

Dylan Chuckry
Dylan Chuckry
2,841 Points
Dylan Chuckry
Dylan Chuckry
2,841 Points

Think about how the input could contain an index of even or odd numbers which means subtracting two from the 0 index won't always give you an even index.