Powers of geometric intersection graphs and dispersion algorithms
✍ Scribed by Geir Agnarsson; Peter Damaschke; Magnús M. Halldórsson
- Publisher
- Elsevier Science
- Year
- 2003
- Tongue
- English
- Weight
- 188 KB
- Volume
- 132
- Category
- Article
- ISSN
- 0166-218X
No coin nor oath required. For personal study only.
✦ Synopsis
We study powers of certain geometric intersection graphs: interval graphs, m-trapezoid graphs and circular-arc graphs. We deÿne the pseudo-product, (G; G ) → G * G , of two graphs G and G on the same set of vertices, and show that G * G is contained in one of the three classes of graphs mentioned here above, if both G and G are also in that class and fulÿll certain conditions. This gives a new proof of the fact that these classes are closed under taking power; more importantly, we get e cient methods for computing the representation for G k if k ¿ 1 is an integer and G belongs to one of these classes, with a given representation sorted by endpoints. We then use these results to give e cient algorithms for the k-independent set, dispersion and weighted dispersion problem on these classes of graphs, provided that their geometric representations are given.
📜 SIMILAR VOLUMES
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