JAVA

package stacktest;

/**
 * @Author: zzz
 * @CreateTime: 2017/3/28 10:52
 * @Description: 隊(duì)列特點(diǎn)（先進(jìn)先出），鏈表實(shí)現(xiàn)的隊(duì)列 在隊(duì)頭刪除元素，在隊(duì)尾插入元素。
 * 這樣才能滿足隊(duì)列的特性。
 */
public class MyQueue<T> {
    private Node<T> front; //隊(duì)列頭，只能刪除元素

     private Node<T> rear; //隊(duì)列尾，只能用來插入入元素

     private int size;//隊(duì)列的長度

 /**
     * 初始化隊(duì)列
 */
 public MyQueue() {
        front = new Node<T>();
        rear = front;
    }

    /**
     * 鏈表的數(shù)據(jù)結(jié)構(gòu)
 */
 private class Node<T> {
        public T data;
        public Node<T> next;

        public Node(T data, Node next) {
            this.data = data;
            this.next = next;
        }

        public Node(T data) {
            this.data = data;
        }

        public Node() {
        }
    }

    public void add(T data) {
        //新插入的節(jié)點(diǎn)永遠(yuǎn)是尾節(jié)點(diǎn)，它的next 指向null(即沒有后繼節(jié)點(diǎn))
         Node newNode = new Node(data, null);
        //讓尾節(jié)點(diǎn)next指向新節(jié)點(diǎn)
         rear.next = newNode;
        rear = newNode;
        size++;
    }

    public T pop() throws Exception {
        if (size < 1) {
            throw new Exception("錯(cuò)誤，隊(duì)列為空。");
        }
        Node<T> nextNode = front.next;

        front.next = nextNode.next;
        size--;
        if (size < 1) {
            rear = front;
            size = 0;
        }
        return nextNode.data;

    }

    //取隊(duì)首元素

 public T peek() throws Exception {
        if (size < 1){
            throw new Exception("錯(cuò)誤，隊(duì)列為空。");
        };
        return front.next.data;

    }
    //返回隊(duì)列的大小
 public int getSize() {
        return size;
    }

    //判斷隊(duì)列是否為空
 public boolean isEmpty() {
        return size == 0;
    }

    /**
     * 遍歷算法，移動(dòng)front指針，直到front指針追上rear指針
 */
 public void   traverse(){
        for(Node currentNode=front.next; currentNode!=null; currentNode=currentNode.next  ){
            System.out.println(currentNode.data);
        }
    }

    public static void main(String[] args)throws Exception{
        MyQueue<String> queue=new MyQueue<>();
        for(int i=0;i<10;i++){
            queue.add("88888-"+i);
        }

       /* for(int i=0;i<10;i++){
            String s=queue.pop();
            System.out.print(s+";");
        }*/
 queue.traverse();

    }
}