Sudoku Rules

Sudoku rules are very simple. Below you can see a typical Sudoku puzzle grid. Initially some cell are filled with random digits. You can't change these digits but you can fill the empty cells. The goal is to fill in the grid in such a way that every row, every column, and every 3x3 box contains all the digits 1 through 9.

Eeah Sudoku puzzle has exactly one proper solution. There is no any math involved, all you need to solve the puzzle is just a simple logic. Here is an example of the solution of the grid above.

Every time you get stuck you can use the "Hint" button to ask computer for help and it will point to cell the correct value of which is easy to find. You can even ask the program to solve the puzzle for you using the "Solve" option. Please note: computer will be able to do this only if you have not made an incorrect decision during your solution process.