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arXiv · 1811.01551

Almost Optimal Distance Oracles for Planar Graphs

Panagiotis Charalampopoulos·Paweł Gawrychowski·Shay Mozes·Oren Weimann
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Abstract

We present new tradeoffs between space and query-time for exact distance oracles in directed weighted planar graphs. These tradeoffs are almost optimal in the sense that they are within polylogarithmic, sub-polynomial or arbitrarily small polynomial factors from the na\"{\i}ve linear space, constant query-time lower bound. These tradeoffs include: (i) an oracle with space $\tilde{O}(n^{1+\epsilon})$ and query-time $\tilde{O}(1)$ for any constant $\epsilon>0$, (ii) an oracle with space $\tilde{O}(n)$ and query-time $\tilde{O}(n^{\epsilon})$ for any constant $\epsilon>0$, and (iii) an oracle with space $n^{1+o(1)}$ and query-time $n^{o(1)}$.

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Panagiotis Charalampopoulos, Paweł Gawrychowski, Shay Mozes, Oren Weimann. 2018-11-05. Almost Optimal Distance Oracles for Planar Graphs. https://arxiv.org/abs/1811.01551

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