PlaySudoku.us
Medium · Puzzle #234
5
9
3
1
4
2
9
3
1
1
3
4
5
9
6
2
8
6
2
2
8
6
4
1
5
4
9
4
8
7
2
9
6
7
5
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.
"Life would be tragic if it weren't funny." — Stephen Hawking
"Life would be tragic if it weren't funny." — Stephen Hawking