public class Person{

    public Person(){}

    public String name = "tom";

    public int age = 1;

    public int sex = 0;

    public void showInfo(){

        System.out.println(this.name);

        System.out.println(this.age);

        System.out.println(this.sex);

    }

    public void seInfo(String name, int age, int sex){

        this.name = name;

        this.age = age;

        this.sex = sex;

    }

}

public class Student extends Person{

    public Student(){

        super();

    }

    public String school;

}