4
9
6
3
8
5
1
4
2
6
3
1
7
9
7
9
1
4
3
8
5
6
4
7
6
8
2
3
3
9
6
1
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.
"Real knowledge is to know the extent of one's ignorance." — Confucius
"Real knowledge is to know the extent of one's ignorance." — Confucius