Finding monochromatic l-shapes in bichromatic point sets
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چکیده
Given a set R of red points and a set B of blue points in the plane of total size n, we study the problem of determining all angles for which there exists an L-shape containing all points from B without containing any points from R. We propose an algorithm to solve the problem in O(n log n) time and O(n) storage. We also describe an output-sensitive algorithm that reports all angles in O(n + k log k) time and O(n) storage, where k is the number of reported angular intervals.
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تاریخ انتشار 2010