Approximation Algorithms for Min UnCut, Min 2CNF Deletion, and Directed Cut Problems
نویسندگان
چکیده
We give O( √ logn)-approximation algorithms for the Min UnCut, Min 2CNF Deletion, Directed Balanced Separator, and Directed Sparsest Cut problems. The previously best known algorithms give anO(logn)-approximation for Min UnCut [9], Directed Balanced Separator [17], Directed Sparsest Cut [17], and an O(logn log logn)approximation for Min 2CNF Deletion [14]. We also show that the integrality gap of an SDP relaxation of the Minimum Multicut problem is Ω(logn).
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