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