Why is it called "byteswap" and not "bytereverse"? "Swapping" can be done in any number of ways, but only one way to reverse.
The Arm architecture does call this operation "reverse bytes", though, so it's not universal to call it "swap".
"Reverses the bytes in the given integer value n."
I would expect the description for "byteswap" to be something like "swaps the given bytes of an integer value n." and be called like byteswap(x, a, b), where a and b are the indicies of the bytes to be swapped.
I didn't mean the std::swap() function itself, but the swapping of two elements a[i] and a[j]. Is there any sorting algorithm that doesn't rely on swapping two elements (or two parts of the array)? I guess, only if the sort is not being done in-place and the result is stored in a different variable/memory.
> does not necessary look like the elements were swapped
The only way elements don't look like they are swapped is elements are changed, added or removed, which doesn't happen during sort.
If you look at the result and at the original, generally you will not find many pairs in which the elements exchanged their positions. It takes special initial arrangements for this to be true for all elements.
You were saying that the final array doesn't have many indices i,j such that a[i] = sorted_a[j] and a[j] = sorted_a[i].
My initial comment was not referring to the final order of the array, but the operations made to reach that order (one or multiple swaps). Another example could have been saying that we could have named the "sort" method "compare" because it uses comparisons in its algorithm (which was a parallel to your initial comment that it's called "swap" because the reverse operation uses swaps to achieve this).