Finding a Length-Constrained Maximum-Density Path in a Tree
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چکیده
Let T = (V, E, w) be an undirected and weighted tree with node set V and edge set E , where w(e) is an edge weight function for e ∈ E . The density of a path, say e1, e2, . . . , ek , is defined as ∑k i=1 w(ei )/k. The length of a path is the number of its edges. Given a tree with n edges and a lower bound L where 1 ≤ L ≤ n, this paper presents two efficient algorithms for finding a maximum-density path of length at least L in O(nL) time. One of them is further modified to solve some special cases such as full m-ary trees in O(n) time.
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تاریخ انتشار 2003