ACI1 constraints

Disuniication is the problem of deciding satissability of a system of equations and disequations w.r.t. a given equational theory. In this paper we study the disuni-cation problem in the context of ACI1 equational theories. We provide a characterization of the interpretation structures suitable to model the axioms in ACI1 theories. The satissability problem is solved using known techniques for the equality constraints and novel methodologies to transform disequation constraints into solved forms. We propose three solved forms, ooering an increasingly more precise characterization of the set of solutions. Two of them can be computed and tested in polynomial time. The novel results achieved open new possibilities in the practical and eecient manipulation of ACI1 constraints.

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