Sudoku 16

Sudoku16 is complicated version of sudoku game destined for real puzzle lovers. It's also known as Suduko, Sudoko, Su do ku, Sodoku, Suduku. In it you must to compare numbers on game board to make them according the rules. Which are very simple. Each row, column and subgrid inibox (4x4) comprises the numbers 1 through 16 or letters A through P or anything else. From children to old can enjoy it for a pass-time.