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