Solving 0-1 Problems in CLP($\cal PB$)

0-1 problems arise in different areas, in particular in artificial intelligence and operations research. For many applications, a simple sub-procedure solving these problems is not sufficient. In this paper, we present the constraint logic programming language CLP(PB) which provides efficient 0-1 constraint solving within the logic programming paradigm. It is well suited for implementing various typical AI problems. CLP(PB) supports pseudo-Boolean constraints, that is equations and inequalities between integer polynomials in 0-1 variables, and pseudo-Boolean optimization, also known as 0-1 programming. We illustrate by example the advantage of pseudo-Boolean formulations versus equivalent ones in propositional logic. We also discuss constraint programming in CLP(PB) and the implementation of algorithms interacting with the current constraint set