Sliding k-Transmitters: Hardness and Approximation
نویسندگان
چکیده
A sliding k-transmitter in an orthogonal polygon P is a mobile guard that travels back and forth along an orthogonal line segment s inside P . It can see a point p ∈ P if the perpendicular from p onto s intersects the boundary of P at most k times. We show that guarding an orthogonal polygon P with the minimum number of k-transmitters is NP-hard, for any fixed k > 0, even if P is simple and monotone. Moreover, we give an O(1)-approximation algorithm for this problem.
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