Note that using different conflict sets for different groups of constraints will often make the search algorithm easier and more efficient. A second allowed form of the r_conflict/2 annotation is Constraint r_conflict ConflictSet-ConflictData. If this is used, ConflictData will appear in the conflict set instead of the Constraint itself. This feature can be used to pass additional information to the search algorithm.fd:(Capacity >= sum(Weights)) r_conflict cap_cstr