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