I cannot believe Dave finds Mark’s answer the most elegant. Ugh. Joe’s solution as he said it to me is pretty similar to how I did it and my math PhD friend (he’s actually a doctor now!) agrees that conceptually it’s the most clean. If you can’t solve it without using just simple concepts, I think it’s clunky. But that’s just me.
I love how people write about how long it took them to solve it. Who cares about whether you’re quicker or slower than other people? Geez.
I’m down to 108 in Minesweeper, by the way. I dunno, if I’m gonna be a hypocrite, just go all out I say.