My last date could invert the binary tree, but with horrendous time complexity (O(n.log(n))).

At that point I knew it wouldn't work out between the two of us so I just got up and left the restaurant. I emailed her the solution later because I'm not an inconsiderate human being.

Imagine dating someone who doesn't even keep snus in their EPA? https://www.youtube.com/watch?v=5hdUKZLQIuQ

Happily married for 5 years. But if I had to do it all over again, would require partner to be able to invert a binary tree.