Using Indexed Finite Set Variables for Set Bounds Propagation

Constraint Programming (CP) has been successfully applied to numerous combinatorial problems Such as scheduling, graph coloring, circuit analysis, or DNA sequencing. Following the success of CP over traditional domains, set variables were also introduced to more declaratively solve a number of different problems. Using a bounds represent at; ion for a finite set variable allows one to compactly represent the solution set of a set constraint problem. Many consistency rnechanisms for maintaining bounds consistency have been proposed and in this paper we propose to use delta domain variable information to speed up constraint propagation. Additionally, we propose the use of indexed set domain variable representations as a better means of improving the use, intuitiveness and efficiency of delta domain variables for propagation tasks.