SUDOKU
Write a number from 1 to 9 into each empty square in the grid so that every number from 1 to 9 appears exactly once in each horizontal row, each vertical column, and each 3×3 block.
4
9
3
6
2
1
7
8
2
3
5
9
5
7
6
6
1
4
7
9
3
1
3
5
* Easy