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