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arXiv · 2408.11368

A Simple Dynamic Spanner via APSP

Rasmus Kyng·Simon Meierhans·Gernot Zöcklein
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Abstract

We give a simple algorithm for maintaining a $n^{o(1)}$-approximate spanner $H$ of a graph $G$ with $n$ vertices as $G$ receives edge updates by reduction to the dynamic All-Pairs Shortest Paths (APSP) problem. Given an initially empty graph $G$, our algorithm processes $m$ insertions and $n$ deletions in total time $m^{1 + o(1)}$ and maintains an initially empty spanner $H$ with total recourse $n^{1 + o(1)}$. When the number of insertions is much larger than the number of deletions, this notably yields recourse sub-linear in the total number of updates. Our algorithm only has a single $O(\log n)$ factor overhead in runtime and approximation compared to the underlying APSP data structure. Therefore, future improvements for APSP will directly yield an improved dynamic spanner.

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Rasmus Kyng, Simon Meierhans, Gernot Zöcklein. 2024-08-21. A Simple Dynamic Spanner via APSP. https://arxiv.org/abs/2408.11368

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