Comment by Tichy

Isn't the Norvig solution completely straightforward? Just the basic back propagation algorithm?

So maybe in some cases it just helps to read the literature a little bit...

For example at the Google Code Competition (forgot the proper name), I am not very good, but I learned some things from reading solutions of older competitions. I think there even is a book dedicated to solving that kind of problem. It would probably help a lot with writing a Sudoku solver, too.

Edit: not to take away from the Norvig solution, it is probably beautifully crafted. But come on - it IS the straightforward solution? Or what am I missing?