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 G 2 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 d
Improved Bandwidth Approximation for Trees and Chordal Graphs
β Scribed by Anupam Gupta
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 110 KB
- Volume
- 40
- Category
- Article
- ISSN
- 0196-6774
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β¦ Synopsis
A linear arrangement of an n-vertex graph G = V E is a one-one mapping f of the vertex set V onto the set n = 0 1 n -1 . The bandwidth of this linear arrangement is the maximum difference between the images of the endpoints of any edge in E G . When the input graph G is a tree, the best known approximation algorithms for the minimum bandwidth linear arrangement (which are based on the principle of volume respecting embeddings) output a linear arrangement which has bandwidth within O log 3 n of the optimal bandwidth. In this paper, we present a simple randomized O log 2 5 n -approximation algorithm for bandwidth minimization on trees. We also show that a close variant of this algorithm gives a similar performance guarantee for chordal graphs.
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