SU-DOKU TOUGHIE
The rules for Su-doku are easy, but this one’s a toughie! Each number from 1 to 9 must appear only once in each horizontal and vertical line, and only once in each 3x3 grid.
The rules for Su-doku are easy, but this one’s a toughie! Each number from 1 to 9 must appear only once in each horizontal and vertical line, and only once in each 3x3 grid.