On Determining the Minimum Length, Tree-Like Resolution Refutation of 2SAT, and Extended 2SAT Formulas

  • K. Subramani
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2550)


This paper is concerned with the design of polynomial time algorithms to determine the shortest length, tree-like resolution refutation proofs for 2SAT and Q2SAT (Quantified 2SAT) clausal systems. Determining the shortest length resolution refutation has been shown to be NP-complete, even for HornSAT systems (for both tree-like and dag-like proofs); in fact obtaining even a linear approximation for such systems is NP-Hard. In this paper we demonstrate the existence of simple and efficient algorithms for the problem of determining the exact number of steps in the minimum length tree-like resolution refutation proof of a 2SAT or Q2SAT clausal system. To the best of our knowledge, our results are the first of their kind.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • K. Subramani
    • 1
  1. 1.LDCSEEWest Virginia UniversityMorgantown

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