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arXiv · 1612.05733

Backdoors to Tractable Valued CSP

Robert Ganian·M. S. Ramanujan·Stefan Szeider
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Abstract

We extend the notion of a strong backdoor from the CSP setting to the Valued CSP setting (VCSP, for short). This provides a means for augmenting a class of tractable VCSP instances to instances that are outside the class but of small distance to the class, where the distance is measured in terms of the size of a smallest backdoor. We establish that VCSP is fixed-parameter tractable when parameterized by the size of a smallest backdoor into every tractable class of VCSP instances characterized by a (possibly infinite) tractable valued constraint language of finite arity and finite domain. We further extend this fixed-parameter tractability result to so-called "scattered classes" of VCSP instances where each connected component may belong to a different tractable class.

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Robert Ganian, M. S. Ramanujan, Stefan Szeider. 2016-12-17. Backdoors to Tractable Valued CSP. https://arxiv.org/abs/1612.05733

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