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