Symmetry declarations for MiniZinc

Abstract. Underlying symmetries in constraint satisfaction and optimization problems can make the search for solutions or optimal solutions much harder. In contrast, when symmetries are known, they can be used to speed up the search for solutions by avoiding considering symmetric parts of the solution space. This can be achieved by using static or dynamic symmetry breaking approaches. Unfortunately symmetry breaking approaches are hard to compare. Each method is typically only implemented in one or two systems, and symmetry papers use different problems to compare and illustrate their ideas. In this paper we show how to add symmetry declarations to MiniZinc models. These symmetries can then either be treated as static symmetry breaking constraints using MiniZinc global decomposition, or passed to a dynamic symmetry breaking method if the underlying solver supports it. This will allow a better understanding of the strengths and weaknesses of different symmetry breaking approaches by al...

• Type: Journal
• Year: 2016
• Where: ACSC
• Authors: Nathaniel Baxter, Geoffrey Chu, Peter J. Stuckey
• Keywords: ACSC 2016, Theoretical Computer Science