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