How to make a strongly connected digraph two-connected

  • A. Frank
  • T. Jordán
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 920)


Given a strongly connected digraph, we give a combinatorial polynomial algorithm for determining a smallest set of new edges to be added to make the graph 2-vertex-connected. The problem was shown to be polynomially solvable in a recent paper [FJ1] for arbitrary starting digraph and any target connectivity k≥1. However, the algorithm relied on the ellipsoid method. Here we further simplify the results of [FJ1] and [Jor3] by some structural statements related to families of ordered pairs of subsets.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • A. Frank
    • 1
  • T. Jordán
    • 1
    • 2
  1. 1.Department of Computer ScienceEötvös UniversityBudapestHungary
  2. 2.CWISJ AmsterdamNetherlands

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