These goals scan the neighborhood nhood. Each leaf node of these goals corresponds to a legal neighbor of the current solution solution.

If specified, nid is used to hold the index and the delta of the neighbor (as with respect to nh.define) instantiated at the current leaf. This can be used to communicate with other goals such as IloNotify and IloTest.

If any applied delta is to be saved back to solution, this must be done explicitly via solution.store(solver), or using IloStoreSolution.

The argument check is used to filter out any unwanted solution deltas received from the neighborhood before instantiation of constrained variables begins. Meta-heuristics automatically supply such a checking object via IloMetaHeuristic::getDeltaCheck. If check is not specified, no additional checking is performed.