An Alternative Eager Encoding of the All-Different Constraint over Bit-Vectors

摘要

A novel eager encoding of the AllDifferent constraint over bit-vectors is presented in this short paper. It is based on 1-to-1 mapping of the input bit-vectors to a linearly ordered set of auxiliary bit-vectors. Experiments with four SAT solvers showed that the new encoding can be solved order of magnitudes faster than the standard encoding in a hard unsatisfiable case.