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