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