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arXiv · 1911.09498

Navigating Planar Topologies in Near-Optimal Space and Time

José Fuentes-Sepúlveda·Gonzalo Navarro·Diego Seco
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Abstract

We show that any embedding of a planar graph can be encoded succinctly while efficiently answering a number of topological queries near-optimally. More precisely, we build on a succinct representation that encodes an embedding of $m$ edges within $4m$ bits, which is close to the information-theoretic lower bound of about $3.58m$. With $4m+o(m)$ bits of space, we show how to answer a number of topological queries relating nodes, edges, and faces, most of them in any time in $\omega(1)$. Further, we show that with $O(m)$ bits of space we can solve all those operations in $O(1)$ time.

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José Fuentes-Sepúlveda, Gonzalo Navarro, Diego Seco. 2019-11-21. Navigating Planar Topologies in Near-Optimal Space and Time. https://doi.org/10.1007/978-3-030-32686-9_35

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