Sudoku

I have been playing Sudoku of late. If you haven't heard of it before, it is actually a logic-based game puzzle. The puzzle is built up by 3x3 blocks. The is a total of 9 blocks with 3x3 cells in every block. There are a few digits filled in the cells initially.

To solve Sudoku, the only thing has to do is just filling up every row, column and block with number ranged from 1 to 9 uniquely.

Try it when you need to tease your brain. :)