On Strongly Connected Digraphs with Bounded Cycle Length
نویسندگان
چکیده
Given a directed graph G = (V;E), a natural problem is to choose a minimum number of the edges in E such that, for any two vertices u and v, if there is a path from u to v in E, then there is a path from u to v among the chosen edges. We show that in graphs having no directed cycle with more than three edges, this problem is equivalent to Maximum Bipartite Matching. This leads to a small improvement in the performance guarantee of the previous best approximation algorithm for the general problem.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 69 شماره
صفحات -
تاریخ انتشار 1996