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

Alejandro Byrne
Alejandro Byrne
2,562 Points
Posted by Alejandro Byrne
Alejandro Byrne
2,562 Points

Challenge not working... I think

Ummm... I think i have everything right. I've completed all the steps except the last one. I checked the last one in workspaces to figure it out, and it worked. But the challenge doesn't say so.. Someone help? The last function has to return the items in index order from least to greatest evens. It should work, don't know why it says it doesn't.

slices.py 
def first_4(thing):
    return thing[0:4]
def first_and_last_4(thing):
    return thing[0:4] + thing[-4:]
def odds(thing):
    return thing[1::2]
def reverse_evens(thing):
    return thing[-2::-2]

1 Answer

James J. McCombie
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.a{fill-rule:evenodd;}techdegree seal-36
James J. McCombie
Python Web Development Techdegree Graduate 21,199 Points
James J. McCombie
.a{fill-rule:evenodd;}techdegree seal-36
James J. McCombie
Python Web Development Techdegree Graduate 21,199 Points

Hello,

the problem is that you do not know the length of the list, if it is an odd number of items, your last function has problems.

I think it's better to start by slicing the list for evens as it is, therefore the length of the list has not affect...

Alejandro Byrne
Alejandro Byrne
2,562 Points
Alejandro Byrne
Alejandro Byrne
2,562 Points

Alright, I solved it. I added an if statement seeing if it was even or odd then doing a specific slice for it. :)