(Nearly-)tight bounds on the contiguity and linearity of cographs

نویسندگان

  • Christophe Crespelle
  • Philippe Gambette
چکیده

In this paper we show that the contiguity and linearity of cographs on n vertices are both O(log n). Moreover, we show that this bound is tight for contiguity as there exists a family of cographs on n vertices whose contiguity is Ω(log n). We also provide an Ω(log n/ log log n) lower bound on the maximum linearity of cographs on n vertices. As a by-product of our proofs, we obtain a min-max theorem, which is worth of interest in itself, stating equality between the rank of a tree and the minimum height of one of its path partitions.

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عنوان ژورنال:
  • Theor. Comput. Sci.

دوره 522  شماره 

صفحات  -

تاریخ انتشار 2014