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