PlaySudoku.us
Medium · Puzzle #12
6
1
5
4
7
8
1
9
4
2
7
1
2
8
5
6
4
7
9
7
2
3
8
5
6
9
7
2
6
7
5
4
2
9
6
1
"What is a proof? It is a demonstration that a statement is necessarily true — a guarantee that no exception can exist." — Henri Poincaré
"What is a proof? It is a demonstration that a statement is necessarily true — a guarantee that no exception can exist." — Henri Poincaré
Scan by digit rather than by cell: find everywhere '7' must go before switching to '8'.
Scan by digit rather than by cell: find everywhere '7' must go before switching to '8'.