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