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