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