Question

How do I reversed or iterate a list using its index?

Here is an example

lst = [3,2,4,1,5]

Output would be: [3,2,4,5,1] (index 3 which is 1 is place in the end)

Another example:

lst = [1,5,4,2,3] 

Output: [1,5,4,3,2] (index 3 which is 2 is place in the end)

It is like the list is been reversed by using slicing.

Answer 1

If you want to reverse the part of a list past a certain point, the most straightforward way would be:

output = (lst[:3] # take the list before element 3
          + # and add
          lst[3:] # the list from element 3 on
          [::-1] # reversed
         )

or, without the comments:

output = lst[:3] + lst[3:][::-1]

If you want to change the existing list, you can:

lst[3:] = lst[3:][::-1]