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