信息管理功能关键算法

package fouth;

import java.util.Comparator;

public class three {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        students [] s = new students[5];
        s[0] = new students("1","张三",20);
        s[1] = new students("3","李四",18);
        s[2] = new students("4","王五",19);
        s[3] = new students("2","赵六",21);
        s[4] = new students("5","陈七",19);
        int count = 0;
        for(int j = 0;j<s.length-1;j++) {
            for(int k = j+1;k<s.length;k++) {
                if(s[j].id.compareTo(s[k].id)>0) {
                    students t;
                    t = s[j];
                    s[j] = s[k];
                    s[k] = t;
                }
            }
        }
        for(int x = 0;x<s.length;x++) {
            System.out.println("学生排序为：学号"+s[x].id +"姓名："+s[x].name+"年龄："+ s[x].age);
        }

        for(int i = 0;i<s.length;i++) {
            if(s[i].age >20) {
                count++;				//统计大于20岁的学生人数
            }
            s[i].age = s[i].age+1;		//给所有学生年龄加1
            System.out.println("所有学生年龄加1：学号"+s[i].id +"姓名："+s[i].name+"年龄："+ s[i].age);

        }

        System.out.println("大于20岁的学生人数："+count);
    }

}
class students{
    String id;		//学号
    String name;	//名字
    int age;		//年龄

    public students() {}
    public students(String id, String name, int age) {
        super();
        this.id = id;
        this.name = name;
        this.age = age;
    }

}