Integration of AI and OR Techniques in Constraint Programming

Abstract

Abstract.A global CP constraint is presented which improves the propagation of reservoir constraints on cumulative resources in schedules with optional tasks. The global constraint is incorporated in a CP approach to solve a Single-Commodity Pickup and Delivery Problem: the Bicycle Rebalancing Problem with Time-Windows and heterogeneous fleet. This problem was recently introduced at the 2015 ACP Summer School on Constraint Programming competition. The resulting CP approach outperforms a Branch-and-Bound approach derived from two closely related problems. In addition, the CP approach presented in this paper resulted in a first place position in the competition.