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