按降序对单链表进行排序

Posted 2023-02-16

【中文标题】按降序对单链表进行排序

【英文标题】：Sort Single Linked List in descending order

【发布时间】：2016-10-16 19:57:23

【问题描述】：

如何按分数降序显示此链接列表？当我在我的 GUI 中显示它以按顶部的最高分排序，然后降到底部的最低分时，我需要它吗？另外，我想知道是否有办法将条目限制为仅 10 个。任何帮助将不胜感激！谢谢。

public class ScoreList 
private Player head; //reference to the head of the list
private Player tail; //reference to the tail of the list
int count;


public ScoreList() 
    count = 0;
            head = null;
            tail = null;


public int getCount()  
    return count;


public int size() 

    int count = 0;
    Player p = head;

    while(p != null) 

        count++;
        p = p.next;
    

    return count;


//method to add an item to the list - append to the tail of the list
public void add(String name, String score)  
    // Create Player object
    Player newPlayer  = new Player(name, score);
    if (head == null) 
        head = newPlayer;
        tail = head;
        count++;
    

    else 
        //append to the end of the list
        tail.setNext(newPlayer);
        tail = newPlayer;
        count++;
    

    if(size() > 10) 

        Player currentPlayer = head;

        for (int i = 0; i < 9; i++) 
            currentPlayer = currentPlayer.next;
        
        currentPlayer.next = null;
    



// end add method


//method to let the user get the data from a node in the list

public String getItem(int index) 
    String result = "";
    String name = "";
    String score = "";
    Player curName;

    if (count > 0 && index == 0) 
        //return the Player info at the head of the list 
        name = head.getName();
        score = head.getScore();
    

    else if (index > 0 && index < count) 
        curName = head;
        for (int i = 1; i <= index; i++) 
            curName = curName.getNext();
         
        name = curName.getName();
        score = curName.getScore();
    

    result = "Player: " + name + " Score: " + score;
    return result;



//nested inner class
public class Player 
       private String player;
       private String score;
       private Player next;

    public Player() 
        player = "";
        score = "";
        next = null;
    

    public Player(String artist, String title) 
        this.player = artist;
        this.score = title;
        next = null;
    

    public String getName() 
        return player;
    

    public String getScore() 
        return score;
    

    public Player getNext() 
        return next;
    

    public void setArtist(String player) 
        this.player = player;
    

    public void setTitle(String score) 
        this.score = score;
    

    public void setNext(Player next) 
        this.next = next;
    








 


 

【问题讨论】：

听起来您需要一个最大优先级队列。有关如何执行此操作的示例，请参见此答案。 ***.com/questions/11003155/…

【参考方案1】：

你为什么把 Score 当作一个字符串？

我假设分数为整数

下面是您可以在 ScoreList 类中包含的排序方法，它将按照玩家得分的降序对您的 LinkList 进行排序。

时间复杂度：O(nlogn) 空间复杂度：O(n)

希望对你有帮助

public void sort() 
    Player runner = head;
    Player[] arr = new Player[size()];
    int i = 0;
    while (runner != null) 
        arr[i++] = runner;
        runner = runner.next;
    

    Arrays.sort(arr, new Comparator<Player>() 

        public int compare(Player o1, Player o2) 
            if (Integer.parseInt(o1.getScore()) > Integer.parseInt(o2.getScore())) 
                return -1;
             else if (Integer.parseInt(o1.getScore()) < Integer.parseInt(o2.getScore())) 
                return 1;
             else 
                return 0;
            
        

    );

    for (int j = 0; j < arr.length - 1; j++) 
        arr[j].setNext(arr[j + 1]);

    
    if (arr.length > 0) 
        arr[arr.length - 1].setNext(null);
        head = arr[0];
        tail = arr[arr.length - 1];