The complexity of recognizing minimally tough graphs

نویسندگان

  • Gyula Y. Katona
  • István Kovács
  • Kitti Varga
چکیده

Let t be a positive real number. A graph is called t-tough, if the removal of any cutset S leaves at most |S|/t components. The toughness of a graph is the largest t for which the graph is t-tough. A graph is minimally t-tough, if the toughness of the graph is t and the deletion of any edge from the graph decreases the toughness. The complexity class DP is the set of all languages that can be expressed as the intersection of a language in NP and a language in coNP. We prove that recognizing minimally t-tough graphs is DP-complete for any positive integer t and for any positive rational number t ≤ 1/2.

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عنوان ژورنال:
  • CoRR

دوره abs/1705.10570  شماره 

صفحات  -

تاریخ انتشار 2017