Trees are ubiquitous objects in any theory in which branching processes occur. Most generally, as a graph, a treeT=(V,E) is a directed, connected graph consisting of a nonempty set of vertices (or nodes), V, and set of edges, E⊆V×V, in which there are no cycles or loops. We...
Improved Hardness of Maximum Common Subgraph Problems on Labeled Graphs of Bounded Treewidth and Bounded Degree We consider the maximum common connected edge subgraph problem and the maximum common connected induced subgraph problem for simple graphs with labeled ver... Tatsuya Akutsu,Avraham A. Melkman...
WLOG presentations, where the underlying graph is a tree, are of central importance in view of Whitehead's Asphericity Conjecture. We present a class of aspherical word labeled oriented graphs. This class can be used to produce highly non-injective aspherical labeled oriented trees and also ...
Tree-optimized labeled directed graphs Article 05 May 2023 References West D B. Introduction to Graph Theory, 2nd ed, NJ: Prentice Hall, Inc, 2001. Google Scholar Gargano M L, Lewinter M, Malerba J F. On the number of increasing nonconsecutive paths and cycles in labelled graphs, Graph...
Introduction A rooted labeled tree with n nodes is a connected graph with n vertices and n Gamma 1 edges where a vertex, the root, is specified. Tight bounds of the width W n of rooted labeled trees with n nodes are given, answering an open question of Odlyzko and Wilf [3] that E(...
Barkauskas and Host [6] showed the problem of determining whether or not an oriented graph has an efficient dominating set is NP-complete. For trees we have the following proposition (see [16], also mentioned in [6]): Proposition 2 For a tree T, each orientation of T can give rise...
This paper develops a decision tree classifier SSC(similarity of same and consistent) for multi-valued and multi-labeled data,improves on MMC's formula for... R Zhao,LI Hong - 《Computer Engineering》 被引量: 11发表: 2007年 Semisupervised Multiclass Classification Problems With Scarcity of Lab...
(n2) token swaps, and thus focus on the problem of minimizing the number of token swaps to reach the target token placement. We give a polynomial-time 2-approximation algorithm for trees, and using this, obtain a polynomial-time 2α-approximation algorithm for graphs whose treeα-spanners ...
Let T be any spanning tree of a graph G=(V,E). Choose an arbitrary leaf vi of T, and let vj be the vertex in V such that f0(vj)=i. Then, we move the token i from the current position vj to its target position vi. Let (w1,w2,…,wq) be a unique path in T from w1=vj...
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