docs: public double evalG(DoubleSolution solution) {
      double g = 0.0;
      for (int var = 1; var < solution.getNumberOfVariables(); var++) {
        g += Math.pow(solution.getVariableValue(var), 2.0) +
          -10.0 * Math.cos(4.0 * Math.PI * solution.getVariableValue(var));
      }
  
      double constant = 1.0 + 10.0 * (solution.getNumberOfVariables() - 1);
      return g + constant;
    }