Enumeration of subtrees of trees
نویسندگان
چکیده
Let T be a weighted tree. The weight of a subtree T1 of T is defined as the product of weights of vertices and edges of T1. We obtain a linear-time algorithm to count the sum of weights of subtrees of T . As applications, we characterize the tree with the diameter at least d, which has the maximum number of subtrees, and we characterize the tree with the maximum degree at least ∆, which has the minimum number of subtrees.
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عنوان ژورنال:
- Theor. Comput. Sci.
دوره 369 شماره
صفحات -
تاریخ انتشار 2006