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arXiv · 2004.05883

A Simple Randomized $O(n \log n)$--Time Closest-Pair Algorithm in Doubling Metrics

Anil Maheshwari·Wolfgang Mulzer·Michiel Smid
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Abstract

Consider a metric space $(P,dist)$ with $N$ points whose doubling dimension is a constant. We present a simple, randomized, and recursive algorithm that computes, in $O(N \log N)$ expected time, the closest-pair distance in $P$. To generate recursive calls, we use previous results of Har-Peled and Mendel, and Abam and Har-Peled for computing a sparse annulus that separates the points in a balanced way.

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Anil Maheshwari, Wolfgang Mulzer, Michiel Smid. 2020-04-13. A Simple Randomized $O(n \log n)$--Time Closest-Pair Algorithm in Doubling Metrics. https://doi.org/10.20382/jocg.v11i1a20

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