People near me are asking how do I solve a Sudoku hard level game in something about 2 minutes, and answering that question it seems to be harder than do it, so here is the explanation.
Basicly, I have 2 ways that I try do do, the first is easy and the otherone is a little bit harder, but I have no idea of which one is faster for a computer solve a game and that's why I'm doing this: Benchmarking!