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