学习基于链表队列的实现

Question

我目前在数据结构 Class 中运行我的基于链表队列的实施项目遇到了一些麻烦 - 我已经构建了所有内容但是我的新列表实例并没有告诉我向我创建的“llq”实例添加演员表。下面是我的 LinkedList class 和我的 Driver Class.

请多关照！这个特别的 subject/topic 有点迷失了 - 我愿意接受任何和所有的反馈 - 谢谢！

  import java.util.LinkedList;

  public class LinkedListQueue {

//Declaring Linked List, Node Head & Tail
LinkedList<String> list; 
Node head;
Node tail;

class Node{
    int data;
    Node prev;
    Node next;

/**
* Node Constructor
* @param data
*/
Node(int d){
    data = d;
}
}

/**
 * Linked List Queue Parameterized Constructor
 * @param list
 */
  public LinkedListQueue(){
    list = new LinkedList<String>();
}

/**
 * Enqueue Method (adds element to tail)
 * @param list
 * @return add
 */
public void enqueue(String string){
    list.add(string);
}

/**
 * Dequeue Method (removes first element)
 * @param list
 * @return removeFirst
 */   
public void dequeue(){
    if(list.isEmpty()){   /*check if linked list is empty*/
        System.out.println("The Queue is Empty.");
    }
    else {
        list.removeFirst();    /*remove first element of linked list*/
    }
}

/**
 * Size Method (Size of queue)
 * @param list
 * @return size
 */ 
public int size(){
    return list.size();    
}

/**
 * Display Method (prints element in queue)
 * @param list
 * @return prints element at the indicated index
 */ 
public void display(){
    for(int i=0;i< list.size();i++){     
        System.out.print(list.get(i)+"  ");   
    }
    System.out.println("\n");
}

/**
 * getHead Method (gets head of the queue)
 * @param list
 * @return first element
 */ 
public String getHead(){

    if(list.isEmpty()){
        return "The Queue is Empty.";
    }
    else {
        return list.getFirst();
    }
}

/**
 * getTail Method (gets tail of the queue)
 * @param list
 * @return last element
 */ 
public String getTail(){

    if(list.isEmpty()){
        return "The Queue is Empty.";
    }
    else {
        return list.getLast();
     }
}

/**
 * IsEmpty Method (checks if queue is empty)
 * @param list
 * @return true/false
 */
public boolean isEmpty(){
    if(list.isEmpty()){     /*checks if linked list is empty*/
        return true;
    }
    else{
        return false;
    }
}

/**
 * Delete Queue Method (clears queue)
 * @param list
 * @return clear
 */ 
public void deleteQueue() {
    list.clear();
}
}



import java.util.LinkedList;
import java.util.PriorityQueue;
import java.util.Queue;


 public class Driver{

   public static void main(String[] args){

       //New instance of linked list queue
       LinkedList llq =new LinkedList();

       //Checking if stack is empty
       System.out.println("Is the Queue empty? " + llq.isEmpty());
       
       llq.addFirst("Queue Element 1");  
       
       llq.enqueue("Queue Element 2");
       llq.enqueue("Queue Element 3");
       llq.enqueue("Queue Element 4");
       llq.enqueue("Queue Element 5");

       System.out.println("The element at the head is: " + llq.getHead());
       
       System.out.println("The element at the tail is: " + llq.getTail());
        
       //Checking size of stack
       System.out.println("Size of the Queue: " + llq.size());
        
       //Printing Stack
       System.out.println("*****Display the Queue*****" );
       llq.display();
            
       llq.addLast("Queue Element 6");  

       llq.dequeue("Queue Element 2");
       llq.dequeue("Queue Element 3");

       //Printing Stack
       System.out.println("*****Display the Queue*****" );
       llq.display();
           
       llq.dequeue("Queue Element 6");  
       llq.dequeue("Queue Element 7");  


           
       //Checking if stack is empty
       System.out.println("Is the stack empty? " + llq.isEmpty());
           
       //Clearing Stack
       llq.deleteQueue();
           
       //Checking if stack is empty
       System.out.println("Is the stack empty? " + llq.isEmpty());
   }
 }

Answer 1

应该是

LinkedListQueue llq = new LinkedListQueue();

而不是因为你不想要一个普通的 LinkedList 而是你自己的包装器。

学习基于链表队列的实现

Learning Linked List Queue Based Implementation

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