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First time using StackOverflow, apologies in-case of any issues.

In python,

list[::-1] returns the reversed list

list[0:len(list)+1] returns the complete list

So why list[0:len(list)+1:-1] returns an empty list?

Further, for a list l= [0,1,2,3,4,5], if I want like [4,3,2]:

Trying l[2:5:-1], returns an empty list. But l[2:5][::-1] works.

Can anyone explain why this is happening? Or what is python actually doing when we slice a list, with a value for step?

Thanks in advance :)

U13-Forward
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Utkarsh Pant
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1 Answers1

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some_list[start:stop:step] means give me elements starting at start and incrementing by step until you hit stop.

Well, if you start at 0 and increment by -1, you never actually reach the stop.

cadolphs
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  • Thank you for answering, it cleared things up but had a follow-up question. For ```l= [0,1,2,3,4,5,6,7,8,9,10]```, why does ```l[0:-6:-1]``` return an empty string? Since it does reach the stop value – Utkarsh Pant Nov 09 '21 at 13:35