MATHEMATICAL ENGINEERING TECHNICAL REPORTS On Odd-Cycle-Symmetry of Digraphs
نویسندگان
چکیده
A digraph is odd-cycle-symmetric if every arc in any elementary odd directed cycle has the reverse arc. This concept arises in the context of the even factor problems, which generalize the path-matching problems. While the even factor problem is NP-hard in general digraphs, it is solvable in polynomial time for odd-cycle-symmetric digraphs. This paper provides a characterization of odd-cycle-symmetric digraphs and presents a linear time algorithm to determine whether a given digraph is odd-cyclesymmetric or not. The paper also discusses the weighted version.
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