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