//
// csp6
// from AR33, figure 18, page 35
//
import static choco.Choco.*;
import choco.cp.model.CPModel;
import choco.cp.solver.CPSolver;
import choco.kernel.model.Model;
import choco.kernel.solver.Solver;
import choco.kernel.solver.ContradictionException;
import choco.kernel.model.variables.integer.IntegerExpressionVariable;
import choco.kernel.model.variables.integer.IntegerVariable;

public class CSP6 {

  
  public static void main(String[] args) throws ContradictionException {

     Model m = new CPModel();

     System.out.println("// model, no variables, no constraints //");
     System.out.println(m.pretty());

     IntegerVariable v1  = makeIntVar("v1",1,5);
     IntegerVariable v2  = makeIntVar("v2",1,5);
     IntegerVariable v3  = makeIntVar("v3",1,5);
     IntegerVariable v4  = makeIntVar("v4",1,5);

     System.out.println("// model, four variables, no constraints //");
     System.out.println(m.pretty());
 
     m.addConstraint(lt(v1,v2));            // v1 < v2
     m.addConstraint(lt(v4,v3));            // v4 < v3
     m.addConstraint(eq(plus(v4,v2),5));    // v4 + v2 = 5
     m.addConstraint(gt(plus(v2,v3),6));    // v2 + v3 > 6
     m.addConstraint(leq(v1,minus(v4,1)));  // v1 <= v4 - 1

     System.out.println("// model, four variables, five constraints, not AC //");
     System.out.println(m.pretty());

     Solver s = new CPSolver();    
     s.read(m);  

     s.propagate();

     System.out.println("// model, four variables, five constraints, AC //");
     System.out.println(m.pretty());

     System.out.println("// solver, four variables, five constraints, AC //");
     System.out.println(s.pretty());


     System.out.println("// solutions, if any //");
     if (s.solve().booleanValue()){
	 System.out.println("v1 = " + s.getVar(v1).getVal() + "  v2 = " + s.getVar(v2).getVal() + 
			    "  v3 = " + s.getVar(v3).getVal() + "  v4 = " + s.getVar(v4).getVal());
	while (s.nextSolution().booleanValue()) 
	    System.out.println("v1 = " + s.getVar(v1).getVal() + "  v2 = " + s.getVar(v2).getVal() + 
			    "  v3 = " + s.getVar(v3).getVal() + "  v4 = " + s.getVar(v4).getVal());
     }
     	
     /*
     s.solve(true);
     System.out.println("feasible: " + s.isFeasible());
     System.out.println("nbSol: " + s.getNbSolutions());
     */
  }
}