{1,2,3,4,5,6,7,8,9,10}
1 2 0
2 1 0
2 3 0
2 4 0
3 2 0
3 5 0
4 2 0
4 6 0
4 5 0
5 3 0
5 4 0
6 4 0
6 7 0
6 8 0
7 6 0
7 8 0
8 6 0
8 7 0
8 9 0
8 10 0
9 8 0
10 8 0
C
B
A