PlaySudoku.us
Expert · Puzzle #524
1
8
5
2
6
3
5
1
1
8
3
2
4
8
5
2
4
6
7
9
6
3
7
1
5
1
Techniques used
- Naked Single
- Hidden Single
- Naked Pair
- X-Wing
- XY-Chain
- XY-Wing
Sudoku was popularized worldwide by Wayne Gould, who spent 6 years writing a computer program to generate puzzles.
Sudoku was popularized worldwide by Wayne Gould, who spent 6 years writing a computer program to generate puzzles.
Competitive Sudoku solvers can hold the full pencil-mark state of a 9×9 grid in working memory, updating it mentally as they go.
Competitive Sudoku solvers can hold the full pencil-mark state of a 9×9 grid in working memory, updating it mentally as they go.