docs: @Override
    public void evaluate(DoubleSolution solution) {
  
      int numberOfVariables = solution.getNumberOfVariables();
      int numberOfObjectives = solution.getNumberOfObjectives();
  
      double[] x = new double[numberOfVariables];
      double[] f = new double[numberOfObjectives];
  
      for (int i = 0; i < numberOfVariables; i++) {
        x[i] = solution.getVariableValue(i);
      }
      // evaluate f
      for (int i = 0; i < numberOfObjectives; i++) {
        f[i] = Math.sqrt(Math.pow(const8[i][0] - x[0], 2) + Math.pow(const8[i][1] - x[1], 2));
      }
  
      for (int i = 0; i < numberOfObjectives; i++) {
        solution.setObjective(i, f[i]);
      }
    }