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