# the description of a 9x9 sudoku instance set DATA := (1, 1, 8) (1, 4, 6) (1, 7, 9) (1, 9, 5) (3, 5, 2) (3, 7, 3) (3, 8, 1) (4, 3, 7) (4, 4, 3) (4, 5, 1) (4, 6, 8) (4, 8, 6) (5, 1, 2) (5, 2, 4) (5, 8, 7) (5, 9, 3) (7, 3, 2) (7, 4, 7) (7, 5, 9) (7, 7, 1) (8, 1, 5) (8, 5, 8) (8, 8, 3) (8, 9, 6) (9, 3, 3) ;