
Unsubscribed User
3,311 PointsError in Setep 4
Hi, I have a question. Why def reverse_evens(let): return (let[::-2])
return Error? If this is a bug or a future.
Best reqards Lukas
def first_4 (let):
return (let[0:4])
def first_and_last_4 (let):
return (let[:4] + let[-4:])
def odds (let):
return (let[1:3])
def reverse_evens(let):
return (let[::-2])
3 Answers

Efaz Khan
5,194 PointsHi, there is a useful function in python called reversed(). Try using that one
def reverse_evens(item):
return list(reversed(item[::2]))

Unsubscribed User
3,311 PointsI know that, but my question was why this function return error? def reverse_evens(let): return (let[::-2])
I tested it in local pycharm and I do not have this problem.

Kailash Seshadri
3,059 PointsI tried the same thing, even in workspaces and got the correct output, but it isnt being accepted in the challenge:
def reverse_evens(item):
rev_even = item [-1::-2]
return rev_even
I tried both item [::-2]
and item [-1::-2]
with it being rejected by the challenge but it works fine in workspaces.

JongHo Kim
8,313 PointsI believe I found out the issue. I had the same problem too, but then I realized that if the number of indexes was odd, counting backwards by two would return the values of the odd indexes. I chose to create a list of the even indexes and then reversed it to avoid this issue.
My solutions are in question_answers.py
Hope this helps!