Advanced Preprocessing for Answer Set Solving

We introduce the first substantial approach to preprocessing in the context of answer set solving. The idea is to simplify a logic program while identifying equivalences among its relevant constituents. These equivalences are then used for building a compact representation of the program (in terms of Boolean constraints). We implemented our approach as well as a SAT-based technique to reduce Boolean constraints. This allows us to empirically analyze both preprocessing types and to demonstrate their computational impact.