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