4
1 1 1
1 2 0
1 3 0
1 4 2
2 1 1
2 2 0
2 3 2
2 4 1
3 1 0
3 2 3
3 3 3
3 4 1
4 1 1
4 2 2
4 3 0
4 4 0
3 2
4 1