On a bidirected relaxation for the MULTIWAY CUT problem
نویسندگان
چکیده
In the Multiway Cut problem, we are given an undirected edge-weighted graph G = (V; E) with c e denoting the cost (weight) of edge e. We are also given a subset S of V , of size k, called the terminals. The objective is to nd a minimum cost set of edges whose removal ensures that the terminals are disconnected. In this paper, we study a bidirected linear programming relaxation of Multiway Cut. We resolve an open problem posed by Vazirani 10], and show that the integrality gap of this relaxation is no better than that for a geometric linear programming relaxation given by CC alinescu et al. 2], and may be strictly worse on some instances.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 150 شماره
صفحات -
تاریخ انتشار 2005