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