Distance Approximating Trees for Chordal and Dually Chordal Graphs
نویسندگان
چکیده
In this paper we show that, for each chordal graph G, there is a tree T such that T is a spanning tree of the square G2 of G and, for every two vertices, the distance between them in T is not larger than the distance in G plus 2. Moreover, we prove that, if G is a strongly chordal graph or even a dually chordal graph, then there exists a spanning tree T of G that is an additive 3-spanner as well as a multiplicative 4-spanner of G. In all cases the tree T can be computed in linear time. Q 1999 Academic Press
منابع مشابه
Distance Approximating Trees for Chordal and Dually Chordal Graphs (Extended Abstract)
In this paper we show that, for each chordal graph G, there is a tree T such that T is a spanning tree of the square G2 of G and, for every two vertices, the distance between them in T is not larger than the distance in G plus 2. Moreover, we prove that, if G is a strongly chordal graph or even a dually chordal graph, then there exists a spanning tree T of G that is an additive 3-spanner as wel...
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