Illuminating Both Sides of Line Segments

  • Csaba D. Tóth
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2098)


What is the minimum number of light sources that can collectively illuminate both sides of n disjoint line segments in the plane? We prove that this optimization problem is NP-hard. The worst case analysis shows, however, that ⌊4(n + 1)/5⌋ light sources are always enough and sometimes necessary for all n ≥2.

This problem was motivated by an open problem posed by Czyzowicz et al.: what is the minimal number of light sources that can collectively illuminate any set of n disjoint segments from one side at least.


Light Source Line Segment Open Problem Problem Complexity Computer Graphic 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Csaba D. Tóth
    • 1
  1. 1.ETH ZürichInstitut fü Theoretische InformatikZürichSwitzerland

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