Modular difference logic is hard

Nikolaj Bjørner; Andreas Blass; Yuri Gurevich; Madan Musuvathi

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arXiv · 0811.0987

Modular difference logic is hard

Nikolaj Bjørner·Andreas Blass·Yuri Gurevich·Madan Musuvathi

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Abstract

In connection with machine arithmetic, we are interested in systems of constraints of the form x + k \leq y + k'. Over integers, the satisfiability problem for such systems is polynomial time. The problem becomes NP complete if we restrict attention to the residues for a fixed modulus N.

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Nikolaj Bjørner, Andreas Blass, Yuri Gurevich, Madan Musuvathi. 2008-11-06. Modular difference logic is hard. https://arxiv.org/abs/0811.0987

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