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