PlaySudoku.us
Hard · Puzzle #49
6
1
7
8
5
2
4
6
8
2
8
4
7
8
1
5
7
3
6
8
4
2
9
3
1
3
"Knowledge is power." — Francis Bacon
"Knowledge is power." — Francis Bacon
The Swordfish technique extends X-Wing to three rows and three columns — rare but decisive on expert grids.
The Swordfish technique extends X-Wing to three rows and three columns — rare but decisive on expert grids.