Edge-Coloring Bipartite Graphs
نویسندگان
چکیده
Given a bipartite graph G with n nodes, m edges and maximum degree ∆, we find an edge coloring for G using ∆ colors in time T +O(m log ∆), where T is the time needed to find a perfect matching in a k-regular bipartite graph with O(m) edges and k ≤ ∆. Together with best known bounds for T this implies an O(m log ∆ + m ∆ log m ∆ log ∆) edge-coloring algorithm which improves on the O(m log ∆+ m ∆ log m ∆ log ∆) algorithm of Hopcroft and Cole. Our algorithm can also be used to find a (∆ + 2)-edge-coloring for G in time O(m log ∆). The previous best approximation algorithm with the same time bound needed ∆ + log ∆ colors.
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عنوان ژورنال:
- J. Algorithms
دوره 34 شماره
صفحات -
تاریخ انتشار 2000