Analyzing approximation algorithms with the dual-fitting method 1 A greedy algorithm for SET COVER
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چکیده
One of the best examples of combinatorial approximation algorithms is a greedy algorithm approximating the (weighted) SET COVER problem. An instance of the SET COVER problem consists of a universe set U = {1, . . . ,m}, a family S = {S1, . . . , Sn} of subsets of U , where set S ∈ S is weighted with wS . We want to find a sub-family of S with minimum total weight such that the union of the sub-family is U (i.e. covers U ). Consider the following greedy algorithm:
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تاریخ انتشار 2005