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

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 نشر من قبل Michiel Smid
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
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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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