Degree constrained submodular flows
نویسندگان
چکیده
We consider the problem of finding a minimum cost 0 − 1 submodular flow with the additional constraint that the sum of the incoming and outgoing flow at each node cannot exceed a given limit. We show that this problem is NP-hard, but it can be approximated in the following sense: we can find a submodular flow of cost not greater than the optimum which violates the additional constraints by at most 1 at every node.
منابع مشابه
Algorithms for Submodular Flows ∗
SUMMARY We first describe fundamental results about submodular functions and submodular flows, which lay a basis for devising efficient algorithms for submodular flows. We then give a comprehensive survey on algorithms for submodular flows and show some possible future research directions.
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