Minimum Vertex Cover in Rectangle Graphs
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چکیده
We consider the Minimum Vertex Cover problem in intersection graphs of axis-parallel rectangles on the plane. We present two algorithms: The first is an EPTAS for non-crossing rectangle families, rectangle families R where R1 \ R2 is connected for every pair of rectangles R1, R2 ∈ R. This algorithm extends to intersection graphs of pseudo-disks. The second algorithm achieves a factor of (1.5 + ε) in general rectangle families, for any fixed ε > 0, and works also for the weighted variant of the problem. Both algorithms exploit the plane properties of axis-parallel rectangles.
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تاریخ انتشار 2010