The minimum degree spanning tree problem on directed acyclic graphs
نویسندگان
چکیده
The minimum degree spanning tree problem has been studied extensively. In this paper, we present a polynomial time algorithm for the minimum degree spanning tree problem on directed acyclic graphs. The algorithm starts with an arbitrary spanning tree, and iteratively reduces the number of vertices of maximum degree. We can prove the algorithm must reduce a vertex of the maximum degree for each phase, and finally result in an optimal tree. The algorithm terminates in O(mnlogn) time, where m and n are the number of edges and vertices respectively. Key–Words: algorithm, spanning tree, directed acyclic graph, polynomial time, minimum degree
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