Tournament pathwidth and topological containment
نویسندگان
چکیده
We prove that for every set S of tournaments the following are equivalent: • there exists k such that every member of S has pathwidth at most k • there is a digraph H such that no subdivision of H is a subdigraph of any member of S • there exists k such that for each T ∈ S, there do not exist k vertices of T that are pairwise k-connected. As a consequence, we obtain a polynomial-time algorithm to test whether a tournament contains a subdivision of a fixed digraph H as a subdigraph.
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 103 شماره
صفحات -
تاریخ انتشار 2013