# Test case.  The resistors are all one-ohm and form the edges of a
#  cube; the voltage feed nodes are diagonally opposite corners of the
#  cube.
#
# By symmetry, the three corners closest to each feed corner are at
#  equal voltages, so we can short them together without effect.  Then
#  the network becomes three resistors in parallel between each feed
#  and its triangle of nearest corners, with six between the two
#  triangles, for a total resistance of 1/3+1/6+1/3=5/6; of the current
#  of 6/5, the ones directly connected to the source and sink carry 1/3
#  of it, or 2/5; the six others each carry 1/6 of it, or 1/5.

# Voltage-supply corners
V 111 1
V 000 0

# Resistors feeding corner 000
R 001 000 1
R 010 000 1
R 100 000 1

# Resistors fed by corner 111
R 111 110 1
R 111 101 1
R 111 011 1

# The other six resistors
R 011 001 1
R 101 001 1
R 011 010 1
R 110 010 1
R 101 100 1
R 110 100 1