Abstract
We consider the problem of searching for a mobile intruder in a circular corridor (a polygon with one polygonal hole) by two searchers, who hold a flashlight. Both searchers move on the outer boundary, directing their flashlights at the inner boundary. The objective is to decide whether there exists a search schedule for the searchers to detect the intruder, no matter how fast he moves. We give a characterization of the class of circular corridors, which are searchable with two flashlights. Based on our characterization, an O(n logn) time algorithm is then presented to determine the searchability of a circular corridor with two flashlights, where n denotes the total number of vertices of the outer and inner boundaries. Moreover, a search schedule can be output in time linear in its size, if it exists. Our result gives the first efficient solution to the polygon search problem for two searchers.
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© 2009 Springer-Verlag Berlin Heidelberg
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Jiang, B., Tan, X. (2009). Searching a Circular Corridor with Two Flashlights. In: Chen, J., Cooper, S.B. (eds) Theory and Applications of Models of Computation. TAMC 2009. Lecture Notes in Computer Science, vol 5532. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-02017-9_37
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DOI: https://doi.org/10.1007/978-3-642-02017-9_37
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-02016-2
Online ISBN: 978-3-642-02017-9
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