location a 0 1
location b 1 0
location c 1 3
location d 3 1
location e 5 0
location f 6 3
location g 5 5
location h 3 4
location i 4 3
distance a b 2
distance a d 6
distance a c 3
distance b d 3
distance c d 6
distance d e 7
distance d h 3
distance d i 6
distance e f 6
distance f g 5
distance f i 3
distance g h 8
distance g i 3
distance h i 2