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ACID-Unification Is NEXPTIME-Decidable

  • Siva Anantharaman
  • Paliath Narendran
  • Michael Rusinowitch
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2747)

Abstract

We consider the unification problem for the equational theory AC(U)ID obtained by adjoining a binary ‘*’ which is distributive over an associative-commutative idempotent operator ‘+’, possibly admitting a unit element U. We formulate the problem as a particular class of set constraints, and propose a method for solving it by using the dag automata introduced by W. Charatonik, that we enrich with labels for our purposes. AC(U)ID-unification is thus shown to be in NEXPTIME.

Keywords

E-Unification Complexity Set constraints Tree automata Dag automata 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Siva Anantharaman
    • 1
  • Paliath Narendran
    • 2
  • Michael Rusinowitch
    • 3
  1. 1.LIFO – OrléansFrance
  2. 2.University at Albany–SUNYUSA
  3. 3.LORIANancyFrance

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