静态变 量

package day11;

class Student{
    private String name; // 姓名
    private int age; // 年龄
    private int sid; // 学号
    public static int numberOfStudent = 0;// 静态变量 用于给学生自动分配学号

    public Student(String name,int age){
        this.name = name;
        this.age = age;
        this.sid = ++numberOfStudent; // 先+1再赋值
    }
    public void show(){  // 学生信息展示
        System.out.println(name + "的年龄是" + age +";学号是：" + sid);
    }
}

public class Static_Exercise {
    public static void main(String[] args){

        Student s1 = new Student("华华",18);
        Student s2 = new Student("古头",20);
        Student s3 = new Student("华子",22);
        Student s4 = new Student("狗子",19);
        Student[] s = {s1,s2,s3,s4};
        for(int i = 0; i < s.length; i++){
            s[i].show();
        }
    }
}