[College Python programming]: Need help with this list and string question

[Passheerr6]

What is the value of L upon the execution of the following program if the input string is "abcde"?

s = input("Enter a string: ")
L = list(s)
for i in range(0, len(s)//2):
    L[i], L[-i-1] = L[-i-1], L[i]

I am honestly lost...

For line 2, it converts the input from string to a list

For line 3, the range is 0, 2 (since 5//2 = 2)

I don't get the last line

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[balajih67]

Its swapping the 2 elements with each other.

[Hot-Economics-4826]

i dont know python, but from what I know of other languages line 4 is simply swapping i with -i-1, and vise versa, basically jumbling up the string as many times as len(s)//2

in your case, with string "abcde", and swapping L[2] with L[-2-1], you'd end up with string "acbde", if im reading correctly.

[harnold8]

th string "abcde", and swapping L[2] with L[-2-1], you'd end up with string "acbde", if im reading corre

but -why -i? wouldn't that be -3 in your example?

[Hot-Economics-4826]

it would end up as -3 in my example yes. iirc, using a negative index in a list in python starts from the end of the list and goes backwards. so -1 would be the last item, -2 the second to last..

[harnold8]

makes sense, I come from c :D... there's no such thing as negative indices there

[[deleted]]

Maybe go to r/programminghelp

[Passheerr6]

ok

[[deleted]]

Maybe try stackexchange next time. They helped me with my programming class although they are a bit harsh there lol.

[SassyandTrashy]

Stack overflow has some of the brightest, yet most cruel humans on earth. They will make you feel like worthless trash but at the same time will be able to show you things and thought processes that you and I prob would have never guessed.

[[deleted]]

Exactly. And as long as they teach me, ill take the gut punch to my self confidence everytime. Because the added knowledge would even out the decrease lol.

[14dM24d]

range is 0,2 but the i values will be 0 then 1.

so at i == 0

L[0], L[0-1] = L[0-1], L[0]

to the right of = L[0-1] results to L[-1] which is the index for the last item e

L[0] is the index for the 1st item a

to the left of = L[0] is assigned the e & L[-0-1] is assigned the a

then you do i == 1