code: package examples;
  
  import org.chocosolver.solver.Solver;
  import org.chocosolver.solver.constraints.IntConstraintFactory;
  import org.chocosolver.solver.search.loop.monitors.IMonitorSolution;
  import org.chocosolver.solver.search.strategy.IntStrategyFactory;
  import org.chocosolver.solver.trace.Chatterbox;
  import org.chocosolver.solver.variables.IntVar;
  import org.chocosolver.solver.variables.VariableFactory;
  
  public class Prova1 {
  
      public void method(){
  	
  	// x + y < 5, where the x ∈ [[0, 5]] and y ∈ [[0, 5]]
  	
  	// 1. Create a Solver
  	Solver solver = new Solver("my first problem");
  	
  	// 2. Create variables through the variable factory
  	IntVar x = VariableFactory.bounded("X", 0, 5, solver);
  	IntVar y = VariableFactory.bounded("Y", 0, 5, solver);
  	
  	// 3. Create and post constraints by using constraint factories
  	solver.post(IntConstraintFactory.arithm(x, "+", y, "<", 5));
  	
  	// 4. Define the search strategy
  	solver.set(IntStrategyFactory.lexico_LB(x, y));
  	
  	// 5. Launch the resolution process
  	solver.findSolution();
  		
  	//6. Print search statistics
  	Chatterbox.printStatistics(solver);
  	
      }
  
      public static void main(String[] args){
  	Prova1 p = new Prova1();
  	
  	p.method();
      }
      
  }
  