abstract class Animal{
    public abstract void makeSound();
}
interface Swimmable {
    void swim ();
}
class Dog extends Animal implements Swimmable {
    @Override
    public void makeSound() {
        System.out.println("汪汪汪！");
    }
    @Override
    public void swim() {
        System.out.println("狗刨式游泳");
    }
}
class Cat extends Animal {
    @Override
    public void makeSound() {
        System.out.println("喵喵喵！");
    }
}
public class AnimalTest {
    public static void main(String[] args) {
        Animal dog = new Dog();
        Animal cat = new Cat();

        System.out.println("=== 动物叫声 ===");
        dog.makeSound();
        cat.makeSound();

        System.out.println("\n=== 游泳测试 ===");
        if (dog instanceof Swimmable) {
            Swimmable s = (Swimmable) dog;
            s.swim();
        }
        if (cat instanceof Swimmable) {
            Swimmable s = (Swimmable) cat;
            s.swim();
        } else {
            System.out.println("猫不会游泳");
        }

    }
}