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

Posted by Mohammadreza Fallah
Mohammadreza Fallah
4,346 Points

my code is not working

My code seems to work well. I tried it on another IDE.

slices.py 
def first_4 (item):
    return item[0:4]
def first_and_last_4 (item):
    return(item[0:4] + item[-4:])
def odds (item):
    i = 0
    s = []
    for j in item:
        if i%2 != 0:
            s.append(j)
        i += 1
    return s
def reverse_evens (item):
    rev_item = item[::-1]
    i = 0
    j = []
    for a in rev_item:
        if i%2 == 0:
            j.append(a)
        i += 1
    return(j)

1 Answer

Christopher Shaw
seal-mask
PLUS
.a{fill-rule:evenodd;}techdegree seal-36
Christopher Shaw
Python Web Development Techdegree Graduate 58,248 Points
Christopher Shaw
.a{fill-rule:evenodd;}techdegree seal-36
Christopher Shaw
Python Web Development Techdegree Graduate 58,248 Points

You almost have it, but have not taken into account that the original list may be odd or even in length.

First you must get the even numberss and then reverse it.

def reverse_evens (item):
    evens = item[::2]
    return evens[::-1]