Abstract
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.
Research was partially supported by the Hungarian National Foundation for Scientific Research, grants OTKA 2118, F014919.
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© 1995 Springer-Verlag Berlin Heidelberg
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Frank, A., Jordán, T. (1995). How to make a strongly connected digraph two-connected. In: Balas, E., Clausen, J. (eds) Integer Programming and Combinatorial Optimization. IPCO 1995. Lecture Notes in Computer Science, vol 920. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-59408-6_69
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DOI: https://doi.org/10.1007/3-540-59408-6_69
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