A Dual-Fitting $\frac{3}{2}$ -Approximation Algorithm for Some Minimum-Cost Graph Problems
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چکیده
We consider a class of graph problems introduced in a paper of Goemans and Williamson that involve finding forests of minimum edge cost. This class includes a number of location/routing problems; it also includes a problem in which we are given as input a parameter k, and want to find a forest such that each component has at least k vertices. Goemans and Williamson gave a 2-approximation algorithm for this class of problems. We give an improved 2 -approximation algorithm.
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