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