LITTLE KNOWN FACTS ABOUT SUDOKU HARD - HARD SUDOKU.

Quads tend to be rarer, and so they’re much less handy in a method since they don’t Allow you to slender down a large number of candidates abruptly, but if you spot a person, it’s value investigating. Solving solitary squares also can change quads into triples or pairs, so don’t forget about these!It's also possible to generate during the m