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        <identifier>oai:drops-oai.dagstuhl.de:12944</identifier>
        <datestamp>2024-03-06T10:51:09Z</datestamp>
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          <dc:title>Improved Approximation Algorithm for Set Multicover with Non-Piercing Regions</dc:title>
          <dc:creator>Raman, Rajiv</dc:creator>
          <dc:creator>Ray, Saurabh</dc:creator>
          <dc:subject>Approximation algorithms</dc:subject>
          <dc:subject>geometry</dc:subject>
          <dc:subject>Covering</dc:subject>
          <dc:description>In the Set Multicover problem, we are given a set system (X,𝒮), where X is a finite ground set, and 𝒮 is a collection of subsets of X. Each element x ∈ X has a non-negative demand d(x). The goal is to pick a smallest cardinality sub-collection 𝒮' of 𝒮 such that each point is covered by at least d(x) sets from 𝒮'. In this paper, we study the set multicover problem for set systems defined by points and non-piercing regions in the plane, which includes disks, pseudodisks, k-admissible regions, squares, unit height rectangles, homothets of convex sets, upward paths on a tree, etc. &#13;
We give a polynomial time (2+ε)-approximation algorithm for the set multicover problem (P, ℛ), where P is a set of points with demands, and ℛ is a set of non-piercing regions, as well as for the set multicover problem (𝒟, P), where 𝒟 is a set of pseudodisks with demands, and P is a set of points in the plane, which is the hitting set problem with demands.</dc:description>
          <dc:publisher>Schloss Dagstuhl – Leibniz-Zentrum für Informatik</dc:publisher>
          <dc:contributor>Rajiv Raman and Saurabh Ray</dc:contributor>
          <dc:date>2020</dc:date>
          <dc:relation>Is Part Of LIPIcs, Volume 173, 28th Annual European Symposium on Algorithms (ESA 2020)</dc:relation>
          <dc:type>InProceedings</dc:type>
          <dc:type>Text</dc:type>
          <dc:type>doc-type:ResearchArticle</dc:type>
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          <dc:identifier>doi:10.4230/LIPIcs.ESA.2020.78</dc:identifier>
          <dc:identifier>urn:nbn:de:0030-drops-129441</dc:identifier>
          <dc:identifier>https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ESA.2020.78</dc:identifier>
          <dc:language>eng</dc:language>
          <dc:rights>https://creativecommons.org/licenses/by/3.0/legalcode</dc:rights>
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