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