Click to select, and then press a number to fill it in. Press space or 0 to delete. Move your mouse to the edge of the screen to toggle easyplace mode. This makes sure you follow the rules of Sudoku. Just use arrow keys to change the varibles.
The rules of Sudoku: There must be one and only one number in each column, row, and square. Try to fill out the whole board. Credits: Sudoku.com for the puzzles. I will try to make a randomized generator soon. All code by me, @Ispyatrain
