vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1
vx
0
1