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