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deque是双端队列，所以它可以在首尾都可以添加数据，操作函数分别为：

push_back：在队列末尾添加一个元素，参数为拷贝或移动的元素

emplace_back c++11 ：在队列尾部添加一个元素

push_front ：在队列头部添加一个元素，参数可以是拷贝或移动的元素

emplace_front c++11 ：在队列头部添加一个元素

resize ：改变容器中可存储元素的个数

下面看代码实现：

#include 
   
    #include 
    
     #include 
     
      using namespace std;class Person{public:    Person(string name):        m_strName(name)    {    }    string m_strName;};void addElement(){    deque
      
        deque1;    string strName =  "《从军行(王昌龄)》青海长云暗雪山，孤城遥望玉门关。黄沙百战穿金甲，不破楼兰终不还！";    Person person(strName);    //int = [-2147483648, 2147483647]    const int count = 214748;//2147483648    double startTime1 = clock();//1计算开始    for(int i = 0; i < count; i++)//214748    {        deque1.push_back(strName);    }    double endTime1 = clock();//1时间结束    cout << "deque1.size=" << deque1.size() << " deque1.max_size=" << deque1.max_size() << endl;    deque1.clear();    cout << "for    1 run time is: " << (double)(endTime1 - startTime1) / CLOCKS_PER_SEC << "s" << endl;    cout << endl;    deque
       
         deque2;    double startTime2 = clock();//2计算开始    for(int i = 0; i < count; i++)//214748    {        deque2.emplace_back(strName);    }    double endTime2 = clock();//2时间结束    cout << "deque2.size=" << deque2.size() << " deque2.max_size=" << deque2.max_size() << endl;    deque2.clear();    cout << "for    2 run time is: " << (double)(endTime2 - startTime2) / CLOCKS_PER_SEC << "s" << endl;    cout << endl;    deque
        
          deque3; double startTime3 = clock();//3计算开始 for(int i = 0; i < count; i++)//214748 { deque3.push_front(strName); } double endTime3 = clock();//3时间结束 cout << "deque3.size=" << deque3.size() << " deque3.max_size=" << deque3.max_size() << endl; deque3.clear(); cout << "for 3 run time is: " << (double)(endTime3 - startTime3) / CLOCKS_PER_SEC << "s" << endl; cout << endl; deque
         
           deque4; double startTime4 = clock();//4计算开始 for(int i = 0; i < count; i++)//214748 { deque4.emplace_front(strName); } double endTime4 = clock();//4时间结束 cout << "deque4.size=" << deque4.size() << " deque4.max_size=" << deque4.max_size() << endl; deque4.clear(); cout << "for 4 run time is: " << (double)(endTime4 - startTime4) / CLOCKS_PER_SEC << "s" << endl; cout << endl; deque
          
            deque5; double startTime5 = clock();//5计算开始 for(int i = 0; i < 2147483; ++i)//214748 { deque5.emplace_front(i); } double endTime5 = clock();//5时间结束 cout << "deque5.size=" << deque5.size() << " deque5.max_size=" << deque5.max_size() << endl; deque5.resize(2147); cout << "deque5.size=" << deque5.size() << " deque5.max_size=" << deque5.max_size() << endl; deque5.clear(); cout << "for 5 run time is: " << (double)(endTime5 - startTime5) / CLOCKS_PER_SEC << "s" << endl; cout << endl; deque
           
             deque6; for(int i = 0; i < 10; ++i)//214748 { deque6.emplace_front(i); } for(auto &val: deque6) { cout << val << "\t"; } cout << endl; cout << "deque6.size=" << deque6.size() << " deque6.max_size=" << deque6.max_size() << endl; deque6.resize(5); cout << "deque6.size=" << deque6.size() << " deque6.max_size=" << deque6.max_size() << endl; for(auto &val: deque6) { cout << val << "\t"; } cout << endl; deque6.resize(11); cout << "deque6.size=" << deque6.size() << " deque6.max_size=" << deque6.max_size() << endl; for(auto &val: deque6) { cout << val << "\t"; } cout << endl; deque6.clear(); cout << endl;}int main(){ addElement(); cout << endl; cout << "Hello World!" << endl; return 0;}
           
          
         
        
       
      
     
    
   

emplace_back/emplace_front和push_back/push_front功能都是向队列中添加新元素，但效率上，emplace_back/emplace_front比push_back/push_front要高些，从以前结果可以看出，因为emplace_back/emplace_front只调用构造函数，没有移动构造函数，也没有拷贝构造函数。

resize重新扩展容器大小，如果重新扩展的容量小于现在的容量，多出的将会丢失，如果大于现在的容量，将会在现有容量的基础上进行扩充，并以0填充默认值。

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