Computer Science and Engineering, Department of


Date of this Version



Technical Report CSL-01-03

Constraint Systems Laboratory
Department of Computer Science and Engineering
University of Nebraska-Lincoln
Lincoln NE 68588-0115


We investigate techniques to enhance the performance of backtrack search procedure with forward-checking (FC-BT) for finding all solutions to a finite Constraint Satisfaction Problem (CSP). We consider ordering heuristics for variables and/or values and bundling techniques based on the computation of interchangeability. While the former methods allow us to traverse the search space more effectively, the latter allow us to reduce it size. We design and compare strategies that combine static and dynamic versions of these two approaches. We show empirically the utility of dynamic variable ordering combined with dynamic bundling in both random problems and puzzles.