  It is shown that the behavior of an $m$-port circuit of maximal monotone
elements can be expressed as a zero of the sum of a maximal monotone operator
containing the circuit elements, and a structured skew-symmetric linear
operator representing the interconnection structure, together with a linear
output transformation. The Condat-V\~u algorithm solves inclusion problems of
this form, and may be used to solve for the periodic steady-state behavior,
given a periodic excitation at each port, using an iteration in the space of
periodic trajectories.
