/*
 隊(duì)列使用時(shí)必須包含頭文件 #include <queue> 有以下幾種方法
 入隊(duì)push(),出隊(duì)pop(), 讀取隊(duì)首元素front(),讀取隊(duì)尾元素back() ，
 判斷隊(duì)是否有元素empty()
 求隊(duì)列元素個(gè)數(shù)size() 
*/
#include <iostream>
#include <queue>
using namespace std;
int main()
{
  queue<int> one;
  one.push(1);
  one.push(2);
  one.push(3);
  cout<<"one 隊(duì)列長(zhǎng)度："<<one.size()<<endl;
  cout<<"隊(duì)尾元素是："<<one.back()<<endl;
  cout<<"隊(duì)頭元素是："<<one.front()<<endl; 
  cout<<"隊(duì)列是否為空(1為空，0為非空)："<<one.empty()<<endl;
  one.pop(); //刪除是從隊(duì)頭元素開(kāi)始的 
  cout<<one.front()<<endl;
  cout<<one.size()<<endl;
  //cout<<one.top()<<endl; //普通隊(duì)列好像沒(méi)有次方法 
  //優(yōu)先隊(duì)列的使用 優(yōu)先隊(duì)列中使用back、front 出現(xiàn)錯(cuò)誤 
  priority_queue<int> three;
  three.push(10);
  three.push(20);
  three.push(30);
  cout<<"three 優(yōu)先隊(duì)列長(zhǎng)度："<<three.size()<<endl;  
  cout<<"隊(duì)列是否為空(1為空，0為非空)："<<three.empty()<<endl;
  while (false == three.empty())
  {
     cout<<three.top()<<endl;
     three.pop();
  }
  cout<<endl;
  system("pause");
  return 0; 
}