RPO Constraint Solving Is in NP

  • Paliath Narendran
  • Michael Rusinowitch
  • Rakesh Verma
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1584)


A new decision procedure for the existential fragment of ordering constraints expressed using the recursive path ordering is presented. This procedure is nondeterministic and checks whether a set of constraints is solvable over the given signature, i.e., the signature over which the terms in the constraints are defined. It is shown that this non-deterministic procedure runs in polynomial time, thus establishing the membership of this problem in the complexity class NP for the first time.


Simple System Function Symbol Ground Term Automate Deduction Unordered Tree 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Paliath Narendran
    • 1
  • Michael Rusinowitch
    • 2
  • Rakesh Verma
    • 3
  1. 1.Institute of Programming and Logics, Department of Computer ScienceState University of New York at AlbanyAlbanyUSA
  2. 2.LORIAVillers les Nancy cedexFrance
  3. 3.Dept. of Comp. ScienceUniversity of HoustonHoustonUSA

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