算法学习(五)---队列

package com.tw.dst.sq; /** * <p>队列是一种先进先出（FIFO）的线性数据结构，常用操作有插入（insert）和删除（remove）</p> * @author tangw 2010-11-27 */ public class Queue { // 队列数组 private long queueArr[]; //队列的前端下标 private int front; //队列的尾端下标 private int rear; //队列的大小 private int maxSize; //队列中元素的个数 private int nItems; //初始化一个大小为size的队列 public Queue(int size){ queueArr = new long[size]; maxSize = size; front = 0; rear = -1; nItems = 0; } //插入操作 public void insert(long value){ //队列已满 if(rear == maxSize-1) rear = -1; queueArr[++rear] = value; nItems++; } //删除操作 public long remove(){ long temp = queueArr[front++]; if(front == maxSize) front = 0; nItems--; return temp; } //返回队列第一个元素 public long peakFront(){ return queueArr[front]; } //判断是否为空 public boolean isEmpty(){ return nItems == 0; } //判断是否已满 public boolean isFull(){ return nItems == maxSize; } //返回队列中元素的个数 public int size(){ return nItems; } public void print(){ for(int i = front;i < front+nItems;i++){ System.out.print(queueArr[i]+" "); } System.out.println(); } public static void main(String[] args) { Queue q = new Queue(10); while(!q.isFull()){ long value = (long)(Math.random()*100); q.insert(value); } q.print(); while(!q.isEmpty()){ q.remove(); q.print(); } q.print(); System.out.println(q.isEmpty()); } }