This first lesson is designed to help you understand the basic concepts in constraint programming. In future lessons, you will work through problems by describing, modeling, and solving problems using IBM® ILOG® Concert Technology and IBM ILOG Solver classes. In this lesson, you are provided with the completed example code so that you can test your installation of Solver.

The following code models and solves the problem introduced in this lesson:

#include <ilsolver/ilosolverint.h>
ILOSTLBEGIN

int main(){
  IloEnv env;
  try {
    IloModel model(env);
    IloIntVar x(env, 5, 12);
    IloIntVar y(env, 2, 17);
    model.add(x + y == 17);
    model.add(x - y == 5);
    IloSolver solver(model);
    if (solver.solve()){
      solver.out() << "x = " << solver.getValue(x) << endl;
      solver.out() << "y = " << solver.getValue(y) << endl;
    }
  }
  catch (IloException& ex) {
    cout << "Error: " << ex << endl;
  }
  env.end();
  return 0;
}