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