漫画算法）Note3）实现队列

参考漫画算法P48

package com.hzc.comicAlgorithm;


public class MyQueue {

    private int[] array;
    private int front;
    private int rear;

    public MyQueue(int capacity) {//初始化一个数组作为队列,capacity n.容量
        this.array = new int[capacity];
    }

    
    public void enQueue(int element) throws Exception {
        if ((rear+1)%array.length == front) {//队列实际长度为数组长度减1
            throw new Exception("队列已满");
        }
        array[rear] = element;
        rear = (rear+1)%array.length;//循环数组的关键.rear代替链表的last指针,记录队尾的数组下标
    }

    
    public int deQueue() throws Exception {
        if (rear == front) {
            throw new Exception("队列已空");
        }
        int delElement = array[front];
        front = (front+1)%array.length;//循环数组的关键,front代替链表中的头指针,记录对头的数组下标
        return delElement;
    }

    
    public void output(){
        for (int i=front; i!=rear; i=(i+1)%array.length) {
            System.out.println(array[i]);
        }
    }

    public static void main(String[] args) throws Exception {
        MyQueue queue = new MyQueue(10);
        queue.enQueue(1);
        queue.enQueue(2);
        queue.enQueue(3);
        queue.enQueue(4);
        queue.enQueue(5);
        queue.enQueue(6);
        queue.enQueue(7);
        queue.enQueue(8);
        queue.enQueue(9);
        queue.deQueue();
        queue.deQueue();
        queue.deQueue();
        queue.deQueue();
        queue.deQueue();
        queue.output();
    }
}