source	target	weight
A	B	1
A	F	4
A	G	2
B	C	10
B	G	2
C	D	4
C	H	6
D	F	7
D	H	5
F	G	3
F	H	8
G	H	9
A	L	1
J	F	4
V	G	2
I	C	10
L	G	2
C	L	4
P	H	6
I	F	7
B	H	5
P	G	3
X	Z	8
Z	H	9