7
0 22 21 16 12 15 15 
22 0 7 8 10 7 7 
21 7 0 7 13 8 8 
16 8 7 0 12 7 7 
12 10 13 12 0 9 5 
15 7 8 7 9 0 4 
15 7 8 7 5 4 0