Best lower bound for the maximum heterochromatic matchings in edge-colored bipartite graphs
نویسندگان
چکیده
Let (B,C) be an (edge-)colored bipartite graph with bipartition (X,Y ), i.e., B is assigned a mapping C : E(B) → {1, 2, · · · , r}, the set of colors. A matching of B is called heterochromatic if its any two edges have different colors. Let N (S) denote a maximum color neighborhood of S ⊆ V (B). We show that if |N (S)| ≥ |S| for all S ⊆ X, then B contains a heterochromatic matching with cardinality at least ⌈ |X| 2 ⌉. Examples are given to show that the lower bound is best possible. This result improves previous results of Li, Li, Liu and Wang.
منابع مشابه
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