Approximation Algorithms for Free-Label Maximization

  • Mark de Berg
  • Dirk H. P. Gerrits
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6139)


Inspired by air traffic control and other applications where moving objects have to be labeled, we consider the following (static) point labeling problem: given a set P of n points in the plane and labels that are unit squares, place a label with each point in P in such a way that the number of free labels (labels not intersecting any other label) is maximized. We develop efficient constant-factor approximation algorithms for this problem, as well as PTASs, for various label-placement models.


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© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Mark de Berg
    • 1
  • Dirk H. P. Gerrits
    • 1
  1. 1.Department of Mathematics and Computer ScienceTechnische Universiteit EindhovenThe Netherlands

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