Sudoku

How To Play

Select difficulty level
Fill the cells with numbers from 1 to 9
Pick a number by clicking a cell (with the mouse) or a keyboard [1-9] key
Delete a number by clicking a cell's (x) button or pressing the 'Delete' key while the mouse is over the cell
The board has 9 regions, each has 9 cells
Rule 1 - each region consists of unique numbers (1-9)
Rule 2 - each row of the board consists of unique numbers (1-9)
Rule 3 - each column of the board consists of unique numbers (1-9)