Reply to Message

Fred XOR Wilma...

Hmmm I'm seeing a difficulty here....

That's not counting the fact that all you've done is express the problem without using at least one extra store.
Given implementing the operation would reguire at least one temporary variable, why would you bother not expressing it in it's simplest form
t = y
y = x
x = t

If anyone gave me that as solution to swapping two variables they'd fail big style in my book.

You'll be doing recursion where iteration would do the job, next.

Programming is a practical real world exrcise, not some quasi-intellectual game.