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