A Faster 4-Approximation Algorithm for the Unit Disk Cover Problem
نویسندگان
چکیده
Given a set P of n points in the plane, we consider the problem of covering P with a minimum number of unit disks. This problem is known to be NP-hard. We present a simple 4-approximation algorithm for this problem which runs in O(n log n)-time and uses the plane-sweep technique. Previous algorithms that achieve the same approximation ratio have a higher time complexity. We also show how to extend this algorithm to other metrics, and to three dimensions.
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