Although we have a lot of challenges where swapping two items in a list is a subtask, like Single swaps of an array; Swap to Sort an Array; \$n\$ swaps into a nop; etc., we don't have the simple challenge of just swapping two items given a list and two indices.
A list with some positive integers \$L\$, and two indices \$a\$ and \$b\$.
The same list, with the two items at the given indices swapped.
- The input-list is guaranteed to contain at least two items.
- The input-list is guaranteed to only contain positive integers.
- The input-indices can be either 0-based or 1-based (please specify in your answer which of the two you've used).
- The input-indices are guaranteed to be valid indices based on the length of the input-list.
- The input-indices are distinct, so will never be the same index. (The values in the input-list won't necessarily be distinct.)
- You can assume \$a<b\$ (and you're allowed to take the inputs in reversed order if it helps).
- I/O is flexible. You're allowed to take the input as a list/array/stream, from STDIN, as a delimited string, etc. You're allowed to modify the input-list directly, or return a new one with the two items swapped.
- This is code-golf, so the shortest answer in bytes wins.
Don't let code-golf languages discourage you from posting answers with non-codegolfing languages. Try to come up with an as short as possible answer for 'any' programming language.
- Standard rules apply for your answer with default I/O rules, so you are allowed to use STDIN/STDOUT, functions/method with the proper parameters and return-type, full programs. Your call.
- Default Loopholes are forbidden.
- If possible, please add a link with a test for your code (e.g. TIO).
- Also, adding an explanation for your answer is highly recommended.
All test cases use 0-based indices.
Inputs: L=[1,2,3,4,5,6,7,8,9,10], a=3, b=7 Output: [1,2,3,8,5,6,7,4,9,10] Inputs: L=[ 3, 8, 1, 4,10,10,10,10], a=0, b=5 Output: [10, 8, 1, 4,10, 3,10,10] Inputs: L=[5,1,4,2,3], a=0, b=4 Output: [3,1,4,2,5] Inputs: L=[5,6], a=0, b=1 Output: [6,5] Inputs: L=[2,2,2], a=0, b=1 Output: [2,2,2]