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arXiv · 1908.05445

Tracking Paths in Planar Graphs

David Eppstein·Michael T. Goodrich·James A. Liu·Pedro Matias
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Abstract

We consider the NP-complete problem of tracking paths in a graph, first introduced by Banik et. al. [3]. Given an undirected graph with a source $s$ and a destination $t$, find the smallest subset of vertices whose intersection with any $s-t$ path results in a unique sequence. In this paper, we show that this problem remains NP-complete when the graph is planar and we give a 4-approximation algorithm in this setting. We also show, via Courcelle's theorem, that it can be solved in linear time for graphs of bounded-clique width, when its clique decomposition is given in advance.

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David Eppstein, Michael T. Goodrich, James A. Liu, Pedro Matias. 2019-08-15. Tracking Paths in Planar Graphs. https://arxiv.org/abs/1908.05445

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