ICALP 1985: Automata, Languages and Programming pp 328-337

# Routing through a generalized switchbox

• Michael Kaufmann
• Kurt Mehlhorn
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 194)

## Abstract

We present an algorithm for the routing problem for two-terminal nets in generalized switchboxes. A generalized switchbox is any subset R of the planar rectangular grid with no non-trivial holes, i.e. every finite face has exactly four incident vertices. A net is a pair of nodes of non-maximal degree on the boundary of R. A solution is a set of edge-disjoint paths, one for each net.

Our algorithm solves generalized switchbox routing problems in time O(n(log n)2) where n is the number of vertices of R, i.e. it either finds a solution or indicates that there is none.

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