Sudoku

Fill-in the missing numbers on the board, so that each row, each column and each 3x3 box has the numbers from 1 to 9 appearing only once.

9 7 8 6
2 4 3 7 8 1
5 1 4 6 9
1 5 9 8 7
3 8 4 6 5 9 1 2
2 6 7 1 5 4 8
3 9 2 4
2 5 7 3 9 6
5 1 8 2 7

Difficulty:

00:00