This paper presents insertions-only algorithms for maintaining the exact andror approximate size of the minimum edge cut and the minimum vertex cut of a graph. ลฝ . The algorithms output the approximate or exact size k in time O 1 and a cut of size k in time linear in its size. For the minimum edge
NOTE Improved Approximation Algorithms for Weighted 2- and 3-Vertex Connectivity Augmentation Problems
โ Scribed by Michal Penn; Haya Shasha-Krupnik
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 126 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0196-6774
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โฆ Synopsis
The problem of finding a minimum augmenting edge-set to make a graph k-vertex connected is considered. This problem is denoted as the minimum k-augmentation problem. For weighted graphs, the minimum k-augmentation problem is NP-complete. Our main result is an approximation algorithm with a performance ratio of 3 for solving the minimum 3-augmentation problem. This improves the best previously known performance guarantee of 11r3. We also have the following marginal result: an approximation algorithm for the minimum 2-augmentation problem that achieves a factor of 2, and thus improves the previously known factor ลฝ . of 2 q 1rn , with n as the number of vertices in the graph.
๐ SIMILAR VOLUMES
The problem of finding a minimum weight k-vertex connected spanning sub-ลฝ . graph in a graph G s V, E is considered. For k G 2, this problem is known to be NP-hard. Combining properties of inclusion-minimal k-vertex connected graphs ลฝ and of k-out-connected graphs i.e., graphs which contain a vertex