Rerouting shortest paths in planar graphs

Paul Bonsma

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arXiv · 1204.5613

Rerouting shortest paths in planar graphs

Paul Bonsma

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Abstract

A rerouting sequence is a sequence of shortest st-paths such that consecutive paths differ in one vertex. We study the the Shortest Path Rerouting Problem, which asks, given two shortest st-paths P and Q in a graph G, whether a rerouting sequence exists from P to Q. This problem is PSPACE-hard in general, but we show that it can be solved in polynomial time if G is planar. To this end, we introduce a dynamic programming method for reconfiguration problems.

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Paul Bonsma. 2012-04-25. Rerouting shortest paths in planar graphs. https://arxiv.org/abs/1204.5613

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