On reducing the cut ratio to the multicut problem
نویسنده
چکیده
We compare two multicommodity ow problems, the maximum sum of ow, and the maximum concurrent ow. We show that, for a given graph and a given set of k commodities with speci ed demands, if the minimum capacity of a multicut is approximated by the maximum sum of ow within a factor of , for any subset of commodities, then the minimum cut ratio is approximated by the maximum concurrent ow within a factor of O( ln k).
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