Abstract
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.
The author acknowledges support from the Berlin-Zürich European Graduate Program “Combinatorics, Geometrym, and Computation”.
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Tóth, C.D. (2001). Illuminating Both Sides of Line Segments. In: Akiyama, J., Kano, M., Urabe, M. (eds) Discrete and Computational Geometry. JCDCG 2000. Lecture Notes in Computer Science, vol 2098. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-47738-1_35
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DOI: https://doi.org/10.1007/3-540-47738-1_35
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