coffee_and_syrup_2.dart

class Syrup {
  String name;
  int amount;

  Syrup(this.name, this.amount);
}

class Coffee {
  String beanType;
  int waterAmount;
  bool hot;
  Syrup? syrup;

  Coffee(this.beanType, this.waterAmount, this.hot, [this.syrup]); // optional

  bool isEspresso() {
    return waterAmount <= 50;
  }
}

void main(List<String> args) {
  var coffee1 = Coffee('에티오피아 예가체프', 350, false, Syrup("바닐라", 5));
  var coffee2 = Coffee('콜롬비아 수프리모', 40, true);
  var coffee3 = Coffee('브라질 산토스', 200, true);
}