Sudoku

The objective of the game is to fill number from 1 to 9 in such a way so that no two same numbers fill in same row, column and 3 x 3 square. For ex. Number 4 should not be fill in same row where 4 is already store. There are 3 x 3 square matrix each matrix must contain 1 to 9 number. The puzzle can be filling with previously available data.