多态的运行

public class Duotai {
    void eat(){
        System.out.println("动物在进食");
    }
    void roam(){
        System.out.println("动物在活动");
    }
    public static void main(String[] args){
        Duotai[] animals = new Duotai[3];
        animals[0] = new Lions();
        animals[1] = new Hippo();
        animals[2] = new Wolf();
        for(int i = 0;i<animals.length;++i){
            animals[i].eat();
            animals[i].roam();
        }
    }
}
class Hippo extends Duotai{
}
class Wolf extends Duotai{
}
class Lions extends Duotai{
}