PlaySudoku.us
Hard · Puzzle #612
1
4
7
3
2
6
6
1
8
9
4
2
5
9
3
4
2
4
3
6
6
2
4
1
5
9
"Chess demands total concentration." — Bobby Fischer
"Chess demands total concentration." — Bobby Fischer
Check columns before rows — columns are often harder to complete and contain more useful constraints.
Check columns before rows — columns are often harder to complete and contain more useful constraints.