What "inverting" a tree means isn't super clear, but the last time this came up on HN it meant reflecting left to right -- right? So the question tests if you c

What "inverting" a tree means isn't super clear, but the last time this came up on HN it meant reflecting left to right -- right? So the question tests if you can write code dealing with recursive data structures at all. To me it's strange to think of this as a niche concern and not something you may do every day.