20
11 19 20 18 12 13 17 15 14 16 
11 13 19 14 15 12 20 18 17 16 
18 16 12 17 20 11 14 15 13 19 
14 13 20 17 15 16 11 18 19 12 
15 16 12 20 11 17 19 13 18 14 
17 15 16 20 12 14 11 19 18 13 
11 14 15 20 16 12 19 18 17 13 
16 18 19 17 13 20 11 15 14 12 
11 13 19 17 16 12 18 20 14 15 
14 18 11 15 19 13 20 17 12 16 
7 10 8 9 4 1 5 3 2 6 
2 3 9 7 6 10 4 5 1 8 
8 6 1 5 10 3 7 4 9 2 
9 1 4 3 6 7 10 5 2 8 
9 6 10 2 5 7 1 8 3 4 
4 5 8 2 9 3 7 1 10 6 
3 6 5 10 9 4 7 2 8 1 
6 8 3 10 2 4 9 1 5 7 
4 2 6 1 8 5 9 10 7 3 
5 4 3 1 6 7 2 10 9 8 
forbidden 1 12
forbidden 1 13
forbidden 1 15
forbidden 1 17
forbidden 2 14
forbidden 2 16
forbidden 2 17
forbidden 3 15
forbidden 3 17
forbidden 3 18
forbidden 4 11
forbidden 4 12
forbidden 4 13
forbidden 4 14
forbidden 4 18
forbidden 5 11
forbidden 5 12
forbidden 5 13
forbidden 5 20
forbidden 6 14
forbidden 6 18
forbidden 7 12
forbidden 7 15
forbidden 8 11
forbidden 8 16
forbidden 8 17
forbidden 9 12
forbidden 9 13
forbidden 9 19
forbidden 9 20
forbidden 10 16
forbidden 10 17