Recognizing the P4-structure of claw-free graphs and a larger graph class
نویسندگان
چکیده
The P4–structure of a graph G is a hypergraph H on the same vertex set such that four vertices form a hyperedge in H whenever they induce a P4 in G. We present a constructive algorithm which tests in polynomial time whether a given 4–uniform hypergraph is the P4–structure of a claw–free graph and of (banner,chair,dart)–free graphs. The algorithm relies on new structural results for (banner,chair,dart)–free graphs which are based on the concept of p–connectedness. As a byproduct, we obtain a polynomial time criterion for perfectness for a large class of graphs properly containing claw–free graphs.
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عنوان ژورنال:
- Discrete Mathematics & Theoretical Computer Science
دوره 5 شماره
صفحات -
تاریخ انتشار 2002