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arXiv · 2405.15811

Maximizing Weighted Dominance in the Plane

Abstract

Let P be a set of n weighted points, Q be a set of m unweighted points in the plane, and k a non-negative integer. We consider the problem of computing a subset $Q'\subseteq Q$ with size at most k such that the sum of the weights of the points of P dominated by at least one point in the set Q' is maximized. A point q in the plane dominates another point p if and only if $x(q)\ge x(p)$ and $y(q)\ge y(p)$, and at least one inequality is strict. We present a solution to the problem that takes O(n + m)-space and $O(k \min\{n+m, \frac{n}{k}+m^2\}\log m)$-time. We (conditionally) improve upon the existing result (the bounds of our solution are interesting when $m= o(\sqrt{n}))$. Moreover, we also present a simple algorithm solving the problem in $O(km^2+n\log m)$-time and $O(n+m)$-space. The bounds of the algorithm are interesting when $m= o(\sqrt{n})$.

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BibTeXRIS

Waseem Akram, Sanjeev Saxena. 2024-05-21. Maximizing Weighted Dominance in the Plane. https://doi.org/10.1007/978-3-031-77019-7_9

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