Polynomial time recognition of P4-structure
نویسندگان
چکیده
A P4 is a set of four vertices of a graph that induces a chordless path; the P4-structure of a graph is the set of all P4’s. Vašek Chvátal asked if there is a polynomial time algorithm to determine whether an arbitrary four-uniform hypergraph is the P4-structure of some graph. The answer is yes; we present such an algorithm.
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