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