PlaySudoku.us
Medium · Puzzle #12
6
1
5
4
7
8
1
9
4
2
7
1
2
8
5
6
4
7
9
7
2
3
8
5
6
9
7
2
6
7
5
4
2
9
6
1
Use pencil marks to track candidates. Eliminating one candidate often triggers a chain reaction.
Use pencil marks to track candidates. Eliminating one candidate often triggers a chain reaction.
Use pencil marks to track candidates. Eliminating one candidate often triggers a chain reaction.
Use pencil marks to track candidates. Eliminating one candidate often triggers a chain reaction.