Hone your skills by solving a grid a day with these sudoku puzzles ranging from easy to hard, created by puzzle master Frank Longo. If you love sudoku, what better way to treat yourself than to set aside a little time for one every day? Tackling the sudoku by puzzle master Frank Longo in this day to day calendar is a rewarding ritual. The rules are simple: fill in the empty squares so that every digit from 1 to 9 appears once (and only once) in every row, column, and 3x3 box. Answers are given on the back of the tear off pages. You?ll find day and date references on every page, as well as major and national holidays, and combined weekend pages. On Mondays, ease into your day with easy ?White Belt? puzzles; the level of difficulty slowly increases as the week goes on, leading up to tricky ?Black Belt? sudoku on the weekend, when you?ve got extra time to take on the challenge.