Approximating k-outconnected subgraph problems

  • Joseph Cheriyan
  • Tibor Jordán
  • Zeev Nutov
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1444)


We present approximation algorithms and structural results for problems in network design. We give improved approximation algorithms for finding min-cost k-outconnected graphs with either a single root or multiple roots for (i) uniform costs, and (ii) metric costs. The improvements are obtained by focusing on single-root k-outconnected graphs and proving (i) a version of Mader's critical cycle theorem and (ii) an extension of a splitting off theorem by Bienstock et al.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Joseph Cheriyan
    • 1
  • Tibor Jordán
    • 2
  • Zeev Nutov
    • 1
  1. 1.Department of Combinatorics and OptimizationUniversity of WaterlooWaterlooCanada
  2. 2.Institut for Matematik og DatalogiOdense UniversitetOdenseDenmark

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