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Partially Walking a Polygon

Authors Franz Aurenhammer, Michael Steinkogler, Rolf Klein

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Author Details

Franz Aurenhammer
  • Institute for Theoretical Computer Science, University of Technology, Graz, Austria
Michael Steinkogler
  • Institute for Theoretical Computer Science, University of Technology, Graz, Austria
Rolf Klein
  • Universität Bonn, Institut für Informatik, Bonn, Germany

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Franz Aurenhammer, Michael Steinkogler, and Rolf Klein. Partially Walking a Polygon. In 29th International Symposium on Algorithms and Computation (ISAAC 2018). Leibniz International Proceedings in Informatics (LIPIcs), Volume 123, pp. 60:1-60:9, Schloss Dagstuhl - Leibniz-Zentrum für Informatik (2018)


Deciding two-guard walkability of an n-sided polygon is a well-understood problem. We study the following more general question: How far can two guards reach from a given source vertex while staying mutually visible, in the (more realistic) case that the polygon is not entirely walkable? There can be Theta(n) such maximal walks, and we show how to find all of them in O(n log n) time.

Subject Classification

ACM Subject Classification
  • Theory of computation → Design and analysis of algorithms
  • Polygon
  • guard walk
  • visibility


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