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