SAT-Based Local Improvement for Finding Tree Decompositions of Small Width

  • Johannes K. Fichte
  • Neha Lodha
  • Stefan Szeider
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10491)


Many hard problems can be solved efficiently for problem instances that can be decomposed by tree decompositions of small width. In particular for problems beyond NP, such as #P-complete counting problems, tree decomposition-based methods are particularly attractive. However, finding an optimal tree decomposition is itself an NP-hard problem. Existing methods for finding tree decompositions of small width either (a) yield optimal tree decompositions but are applicable only to small instances or (b) are based on greedy heuristics which often yield tree decompositions that are far from optimal. In this paper, we propose a new method that combines (a) and (b), where a heuristically obtained tree decomposition is improved locally by means of a SAT encoding. We provide an experimental evaluation of our new method.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Johannes K. Fichte
    • 1
  • Neha Lodha
    • 1
  • Stefan Szeider
    • 1
  1. 1.TU WienViennaAustria

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