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Marie Lu
179 PointsWhy does this not go in reverse evens?
For some reason this does not work in challenges, while it works in workspaces. I am reversing in evens. It starts from -1th index and then increments by -2 making it go backwards
def reverse_evens(item):
list(item)
return item[-1: :-2]
People online have said to use the following, it works... I just don't know how and why because my solution seems perfectly fine as well..
return item[::2] and item[::-1]
2 Answers
juliansteffen
9,802 PointsDear Marie,
did you try? print(reverse_evens("hello")) It should be olleh your code gives => olh
might this will help you to solve the problem. https://stackoverflow.com/questions/509211/explain-slice-notation
Greetings Julian
juliansteffen
9,802 PointsDear Marie,
the Problem is by your solution.
def reverse_evens(item): list(item) return item[-1: :-2]
print(reverse_evens([1,2,3,4,5])) [5, 3, 1] print(reverse_evens([1,2,3,4,5,6])) [6, 4, 2]
your solution can't handle list with even length. Might you have now a point to think about it again.
Greetings Julian
juliansteffen
9,802 Pointsjuliansteffen
9,802 PointsAnd => return item[::2] and item[::-1] works but is not 100% "correct" one part is unnecessary
Marie Lu
179 PointsMarie Lu
179 PointsThanks Julian Steffen However, I'm still not able to figure out why my code went wrong.. it starts from -1 and goes by backwards in two increments.. this worked in workspaces! How is going two increments and then -1 going to make it go even and that too reverse?