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On vertex ranking of a starlike graph

✍ Scribed by Sun-yuan Hsieh


Publisher
Elsevier Science
Year
2002
Tongue
English
Weight
76 KB
Volume
82
Category
Article
ISSN
0020-0190

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✦ Synopsis


A vertex coloring c : V β†’ {1, 2, . . . , t} of a graph G = (V , E) is a vertex t-ranking if for any two vertices of the same color every path between them contains a vertex of larger color. The vertex ranking number Ο‡ r (G) is the smallest value of t such that G has a vertex t-ranking. A Ο‡ r (G)-ranking of G is said to be an optimal vertex ranking. In this paper, we present an O(|V | + |E|) time algorithm for finding an optimal vertex ranking of a starlike graph G = (V , E). Our result implies that an optimal vertex ranking of a split graph can be computed in linear time.


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