0 -> X1
X1 -> 0
0 -> X1
0 -> X1
0 -> Y1
Y1 -> 0
0 -> Z1
Z1 -> 0
0 -> V1
V1 -> 0
0 -> X2
X2 -> 0
0 -> X2
0 -> X2
0 -> Y2
Y2 -> 0
0 -> Z2
Z2 -> 0
0 -> V2
V2 -> 0