Eecient Minimum Spanning Tree Construction without Delaunay Triangulation
نویسندگان
چکیده
Minimum spanning tree problem is a very important problem in VLSI CAD. Given n points in a plane, a minimum spanning tree is a set of edges which connects all the points and has a minimum total length. A naive approach enumerates edges on all pairs of points and takes at least (n 2) time. More eecient approaches nd a minimum spanning tree only among edges in the Delaunay triangulation of the points. However, Delaunay triangu-lation is not well deened in rectilinear distance. In this paper, we rst establish a framework for minimum spanning tree construction which is based on a general concept of spanning graphs. A spanning graph is a natural deenition and not necessarily a Delaunay triangulation. Based on this framework, we then design an O(n log n) sweep-line algorithm to construct a rectilinear minimum spanning tree without using Delaunay triangulation.
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