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