PlaySudoku.us
Hard · Puzzle #717
7
6
5
6
8
9
1
9
4
5
6
4
7
3
4
4
3
2
6
9
1
2
8
5
8
7
4
After placing a digit, immediately check its row, column, and box for new naked singles.
After placing a digit, immediately check its row, column, and box for new naked singles.
If pointing pairs aren't visible, try box-line reduction. They're inverses — if one fails, try the other.
If pointing pairs aren't visible, try box-line reduction. They're inverses — if one fails, try the other.