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

Posted by Sadie K
Sadie K
3,745 Points

I can't get past this question, I'm getting a generic "Try again!" message.

Here's my code

def reverse_evens(list): list.sort() if list[-1] % 2 == 0: return list[-1::-2] else: return list[-2::-2]

slices.py 
def first_4(list):
    return list[0:4] 
def first_and_last_4(list):
    list = list[0:4] + list[len(list)-4:len(list)]
    return list

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

def reverse_evens(list):
    list(list)
    list.sort()
    if list[-1] % 2 == 0:
        return list[-1::-2]
    else:
        return list[-2::-2]

1 Answer

Ernestas Petruoka
Ernestas Petruoka
1,856 Points
Ernestas Petruoka
Ernestas Petruoka
1,856 Points

Well first of all I would change given argument in your code, because list are function to make a list and I don't know for sure if it's good to use that as argument. Then if you make a list from a string you need to use variable in which you do that for example l = list(argument). Also you don't need sort list. Then you check not the last index value in list, but lenght of the list (if it's even or odd lenght long). So you need use if len(list) % 2 == 0:, not if list[-1] % 2 == 0. And the last problem is that you need change places in return's. If len(list) % 2 == 0: you need return list[-2::-2] else return return list[-1::-2].

The code should look like this:

def reverse_evens(iterable):
    l =list(iterable)
    if len(l) % 2 == 0:
        return l[-2::-2]
    else:
        return l[-1::-2]

Hope that will help you ! BTW Sory if I made some grammar mistakes, still learning english :)

Sadie K
Sadie K
3,745 Points

Thanks! This solved my issue. I see how you were able to handle this problem.