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Position-Independent Street Searching

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Algorithms and Data Structures (WADS 1999)

Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 1663))

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Abstract

A polygon P is a street if there exist points (u,v) on the boundary such that P is weakly visible from any path from u to v. Optimal strategies have been found for on-line searching of streets provided that the starting position of the robot is s = u and the target is located at t = v. Thus a hiding target could foil the strategy of the robot by choosing its position t in such a manner as not to realize a street. In this paper we introduce a strategy with a constant competitive ratio to search a street polygon for a target located at an arbitrary point t on the boundary, starting at any other arbitrary point s on the boundary. We also provide lower bounds for this problem. This makes streets only the second non-trivial class of polygons (after stars) known to admit a constant-competitive-ratio strategy in the general position case.

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© 1999 Springer-Verlag Berlin Heidelberg

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Bröcker, C.A., López-Ortiz, A. (1999). Position-Independent Street Searching. In: Dehne, F., Sack, JR., Gupta, A., Tamassia, R. (eds) Algorithms and Data Structures. WADS 1999. Lecture Notes in Computer Science, vol 1663. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-48447-7_25

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  • DOI: https://doi.org/10.1007/3-540-48447-7_25

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-66279-2

  • Online ISBN: 978-3-540-48447-9

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