PlaySudoku.us
Medium · Puzzle #571
4
5
3
7
5
9
1
3
4
7
3
8
4
9
2
8
4
1
7
6
5
2
4
3
6
8
4
1
5
2
7
8
4
6
9
"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'.