Ch. 4 Problem 31
r8 3 4 8
r4 4 0 4
r2 5 4 2
r10 6 5 10
r3 5 0 3
r5 6 0 5
 * vprobe 5 4 0
i8 5 6 8
v100 3 0 100
 * .dc v100 100 100 1
.op
 * .print v(3) v(4) v(5) v(6)
.end