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A Constant Approximation for Colorful k-Center

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 نشر من قبل Shreyas Pai
 تاريخ النشر 2019
  مجال البحث الهندسة المعلوماتية
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In this paper, we consider the colorful $k$-center problem, which is a generalization of the well-known $k$-center problem. Here, we are given red and blue points in a metric space, and a coverage requirement for each color. The goal is to find the smallest radius $rho$, such that with $k$ balls of radius $rho$, the desired number of points of each color can be covered. We obtain a constant approximation for this problem in the Euclidean plane. We obtain this result by combining a pseudo-approximation algorithm that works in any metric space, and an approximation algorithm that works for a special class of instances in the plane. The latter algorithm uses a novel connection to a certain matching problem in graphs.

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