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arXiv · 1706.01508

Time-dependent shortest paths in bounded treewidth graphs

Glencora Borradaile·Morgan Shirley
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Abstract

We present a proof that the number of breakpoints in the arrival function between two terminals in graphs of treewidth $w$ is $n^{O(\log^2 w)}$ when the edge arrival functions are piecewise linear. This is an improvement on the bound of $n^{\Theta(\log n)}$ by Foschini, Hershberger, and Suri for graphs without any bound on treewidth. We provide an algorithm for calculating this arrival function using star-mesh transformations, a generalization of the wye-delta-wye transformations.

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Glencora Borradaile, Morgan Shirley. 2017-06-05. Time-dependent shortest paths in bounded treewidth graphs. https://arxiv.org/abs/1706.01508

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