منابع مشابه
Constructing the Maximum Consensus Tree from Rooted Triples
We investigated the problem of constructing the maximum consensus tree from rooted triples. We showed the NP-hardness of the problem and developed exact and heuristic algorithms. The exact algorithm is based on the dynamic programming strategy and runs in O((m + n2)3n) time and O(2n) space. The heuristic algorithms run in polynomial time and their performances are tested and shown by comparing ...
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Given a graph and a root, the Maximum Bounded Rooted-Tree Packing (MBRTP) problem aims at finding K rooted-trees that span the largest subset of vertices, when each vertex has a limited outdegree. This problem is motivated by peerto-peer streaming overlays in under-provisioned systems. We prove that the MBRTP problem is NP-complete. We present two polynomial-time algorithms that computes an opt...
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A bijection is defined recursively between the set of natural numbers and the set of finite rooted trees. It is based on the prime decomposition of a natural number and the rank of a prime. This bijection leads naturally to a canonical presentation of rooted trees. For trees in each of two classes, bounds are given for the number of nodes in terms of the number assigned to the tree.
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 2012
ISSN: 0166-218X
DOI: 10.1016/j.dam.2012.05.012