集合框架 泛型LinkedList TreeSet

//package LinkedList;

import java.util.*;



public class TryLinkedlist {
    

    public static void main(String args[ ]) {
    

        List<Student> list = new LinkedList<Student>();

        list.add(new Student("张三",86));

        list.add(new Student("李四",83));

        list.add(new Student("赵大龙",89));

        list.add(new Student("李云龙",80));

        Iterator<Student> iter=list.iterator();

        int sum=0;

        System.out.println("排序前,链表中的数据:");

        while(iter.hasNext()){
    

            Student stu=iter.next();

            System.out.println(stu.name+ "成绩:"+stu.score);

        }

        System.out.println("排序（按成绩）后,链表中的数据:");

        /*完善代码：使用Collection类的sort方法排序并输出——注意格式*/
        Collections.sort(list,new Comparator<Student>(){
    
            public int compare(Student o1, Student o2) {
    
                return o1.score-o2.score;
            }
        });
        Iterator<Student> iter2=list.iterator();
        while(iter2.hasNext()){
    
            Student stu=iter2.next();
            sum+=stu.score;
            System.out.println(stu.name+ "成绩:"+stu.score);
        }
        System.out.println("平均成绩:"+sum/list.size());
        /*完善代码：使用Linkedlist类的size方法求平均分——注意格式*/

    }

}



class Student implements Comparable {
    

    String name;

    int score;

    Student(String name,int score) {
    

        this.name=name;

        this.score=score;

    }

    public int compareTo(Object b) {
    

        Student st=(Student)b;

        return (this.score-st.score);

    }

}

//package TreeSet;

import java.util.*;

public class TryTreeSet{
    

    public static void main(String args[]) {
    

        List<Student> list=new LinkedList<Student>();

        int score []={
    65,76,45,99,77,88,100,79};

        String name[]={
    "张三","李四","旺季","加戈","为哈","周和","赵李","将集"};

        for(int i=0;i<score.length;i++){
    

            list.add(new Student(score[i],name[i]));

        }

        Iterator<Student> iter=list.iterator();

        TreeSet<Student> mytree=new TreeSet<Student>();

        while(iter.hasNext()){
    

            Student stu=iter.next();

            mytree.add(stu);

        }

        /*完善代码：将list中的数据输入到树集中*/



        Iterator<Student> te=mytree.iterator();


        /*完善代码：输出树集排序结果*/
        while(te.hasNext()){
    
            Student stu=te.next();
            System.out.println(stu.name+" "+stu.english);
        }

    }

}




class Student implements Comparable {
    

    int english=0;

    String name;

    Student(int english,String name) {
    

        this.name=name;

        this.english=english;

    }

    public int compareTo(Object b) {
    

        Student st=(Student)b;

        return (this.english-st.english);

    }

}