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