PlaySudoku.us
Medium · Puzzle #344
6
9
7
5
3
4
1
2
4
3
1
6
6
5
3
4
6
9
5
7
7
5
6
3
9
8
5
6
7
2
5
9
3
7
5
7
1
There are Sudoku World Championships held annually, with competitors from over 30 countries.
There are Sudoku World Championships held annually, with competitors from over 30 countries.
Always update pencil marks immediately after placing a digit — stale marks cause almost all solving errors.
Always update pencil marks immediately after placing a digit — stale marks cause almost all solving errors.