docs: @Override
    public void evaluate(DoubleSolution solution)  {
      double [] fx = new double[getNumberOfObjectives()];
      
      double x1,x2,x3,x4,x5,x6;
      x1 = solution.getVariableValue(0);
      x2 = solution.getVariableValue(1);
      x3 = solution.getVariableValue(2);
      x4 = solution.getVariableValue(3);
      x5 = solution.getVariableValue(4);
      x6 = solution.getVariableValue(5);
  
      fx[0] = - (25.0*(x1-2.0)*(x1-2.0) +
                    (x2-2.0)*(x2-2.0) + 
                    (x3-1.0)*(x3-1.0) + 
                    (x4-4.0)*(x4-4.0)+
                    (x5-1.0)*(x5-1.0));
                  
      fx[1] = x1*x1 + x2*x2 + x3*x3 + x4*x4 + x5*x5 + x6*x6;
      
      solution.setObjective(0,fx[0]);
      solution.setObjective(1,fx[1]);
  
      this.evaluateConstraints(solution);
    }