In order to be able to search for solutions, a solver (that is, an instance of IloSolver) must save certain information, including the state of solver objects such as:

• the values of all the Solver variables associated with that solver,
• the domains of all the Solver variables associated with that solver,
• all the constraints that have been posted on the variables associated with that solver.

The state of a solver also includes memory usage, object values, any search space already explored, and so on.

States are used during the search for a solution. The most important feature of states is that they can be restored.

In other words, during the execution of a Solver program, a state can be created, then execution proceeds, then that previously created state may be restored. In such a case, we say that Solver backtracks to the previously created state.

See the concepts Choice Point, Propagation, and Reversibility for more information.

See Also

IlcConstraint