Approximating Minimum Feedback Sets and Multicuts in Directed Graphs

@article{Even1998ApproximatingMF,
  title={Approximating Minimum Feedback Sets and Multicuts in Directed Graphs},
  author={Guy Even and Joseph Naor and Baruch Schieber and Madhu Sudan},
  journal={Algorithmica},
  year={1998},
  volume={20},
  pages={151-174}
}
Abstract. This paper deals with approximating feedback sets in directed graphs. We consider two related problems: the weighted feedback vertex set (FVS) problem, and the weighted feedback edge set (FES) problem. In the {FVS} (resp. FES) problem, one is given a directed graph with weights (each of which is at least one) on the vertices (resp. edges), and is asked to find a subset of vertices (resp. edges) with minimum total weight that intersects every directed cycle in the graph. These problems… 

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