[dc443]

It's like a little puzzle snack type of a thing that I've certainly never been lucky enough to need to solve in 15 years of programming yet.

Yes, I think it's really limited in utility. But it can offer some insight into how quick and flexible you are generally speaking.

My first impression is you can do a quick DFS recursive function that does a swap (can prolly use xor operator) on the left & right pointers