public static void decide(double bmi) {
   if (bmi < THRESHOLD_UNDERWEIGHT) {
     SimpleIO.println("Underweight");
   } else if (bmi < THRESHOLD_OVERWEIGHT) {
     SimpleIO.println("Normal weight");
   } else {
     SimpleIO.println("Overweight");
   }
 }
  public static void main(String[] args) {
    double weight;
    double height;
    double bmi;

    SimpleIO.println("Enter weight [kg]");
    weight = SimpleIO.readDouble();
    SimpleIO.println("Enter height [m]");
    height = SimpleIO.readDouble();

    bmi = weight / height / height;

    SimpleIO.println("BMI = " + bmi);
    decide(bmi);
  }