Inapproximability Results for Guarding Polygons and Terrains

@article{Eidenbenz2001InapproximabilityRF,
  title={Inapproximability Results for Guarding Polygons and Terrains},
  author={Stephan Johannes Eidenbenz and Christoph Stamm and Peter Widmayer},
  journal={Algorithmica},
  year={2001},
  volume={31},
  pages={79-113}
}
Abstract. Past research on art gallery problems has concentrated almost exclusively on bounds on the numbers of guards needed in the worst case in various settings. On the complexity side, fewer results are available. For instance, it has long been known that placing a smallest number of guards for a given input polygon is NP -hard. In this paper we initiate the study of the approximability of several types of art gallery problems. Motivated by a practical problem, we study the approximation… 

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