package oop;/** * Created by liuxingwang on 2019/12/17. */public class Main {    public static void main(String[] args) {        Person p = new Person("小米",12);        Student s = new Student("小红",20,99);        PrimaryStudent ps = new PrimaryStudent("小军",9,100,5);        System.out.println(ps.getScore());        System.out.println(ps.getGrade());    }}class Person{    protected String name;    protected int age;    public Person(String name, int age){        this.name = name;        this.age = age;    }    public String getName() { return name; }    public void setName() { this.name = name; }    public int getAge() { return age; }    public void setAge() { this.age = age; }}class Student extends Person {    protected int score;    public Student (String name , int age, int score){        super(name,age);        this.score = score;    }    public int getScore() { return score; }}class PrimaryStudent extends Student {    protected int grade;    public PrimaryStudent(String name , int age , int score , int grade){        super(name,age,score);        this.grade = grade;    }    public int getGrade() { return grade; }}