Resolution of constraints in algebras of rational trees

  • Luis Damas
  • Nelma Moreira
  • Sabine Broda
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 727)


This work presents a constraint solver for the domain of rational trees. Since the problem is NP-hard the strategy used by the solver is to reduce as much as possible, in polynomial time, the size of the constraints using a rewriting system before applying a complete algorithm. This rewriting system works essentially by rewriting constraints using the information in a partial model. An efficient C implementation of the rewriting system is described and an algorithm for factoring complex constraints is also presented.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • Luis Damas
    • 1
  • Nelma Moreira
    • 1
  • Sabine Broda
    • 1
  1. 1.LIACCUniversidade do PortoPortoPortugal

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