How to make a digraph strongly connected


Given a directed graphG, acovering is a subsetB of edges which meets all directed cuts ofG. Equivalently, the contraction of the elements ofB makesG strongly connected. AnO(n 5) primal-dual algorithm is presented for finding a minimum weight covering of an edge-weighted digraph. The algorithm also provides a constructive proof for a min-max theorem due to Lucchesi and Younger and for its weighted version.

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Frank, A. How to make a digraph strongly connected. Combinatorica 1, 145–153 (1981).

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AMS (1980) subject classification

  • 05 C 20, 90 C 10, 05 C 40
  • 68 C 25, 68 E 10