C + + Insert iterator

  
 

   
  

  
#include <iostream>
   
  

  
#include <vector>
   
  

  
#include <list>
   
  

  
#include <iterator>
   
  

  

   
  

  
using namespace std;
   
  

  

   
  

  
template<typename T>
   
  

  
void PrintElements(T c)
   
  

  
{
   
  

  
 typename T::const_iterator itr = c.begin();//在GCC下typename不能省略
   
  

  

   
  

  
 while(itr != c.end())
   
  

  
 {
   
  

  
 cout << *itr++ << " ";
   
  

  
 }
   
  

  
 cout << endl;
   
  

  
}
   
  

  

   
  

  
int main()
   
  

  
{
   
  

  
 vector<int> vecSrc;
   
  

  
 list<int> vecDest;
   
  

  

   
  

  
 for(vector<int>::size_type i = 0; i < 3; ++i)
   
  

  
 {
   
  

  
 vecSrc.push_back(i);
   
  

  
 }//--0,1,2---
   
  

  

   
  

  

   
  

  
 /**
   
  

  
 * 第一种方法是调用<iterator>头文件中的函数来返回一个back_insert_iterator对象
   
  

  
 * template< class Container >
   
  

  
 * std::back_insert_iterator<Container> back_inserter( Container& c );
   
  

  
 */
   
  

  
 /**
   
  

  
 * 第二种方法是调用back_insert_iterator类的构造函数来创建类对象
   
  

  
 * explicit
   
  

  
 * back_insert_iterator(_Container& __x) : container(&__x) { }
   
  

  
 */
   
  

  
 copy(vecSrc.begin(), vecSrc.end(), back_inserter(vecDest));
   
  

  
 //copy(vecSrc.begin(), vecSrc.end(), back_insert_iterator<list<int> >(vecDest));
   
  

  
 PrintElements(vecDest);//--0,1,2---
   
  

  

   
  

  
 copy(vecSrc.begin(), vecSrc.end(), front_inserter(vecDest));
   
  

  
 //copy(vecSrc.begin(), vecSrc.end(), front_insert_iterator<list<int> >(vecDest));
   
  

  
 PrintElements(vecDest);//--2,1,0,0,1,2---
   
  

  

   
  

  
 copy(vecSrc.begin(),vecSrc.end(), inserter(vecDest, ++vecDest.begin()));
   
  

  
 //copy(vecSrc.begin(), vecSrc.end(), insert_iterator<list<int> >(vecDest, ++vecDest.begin()));
   
  

  
 PrintElements(vecDest);//--2,0,1,2,1,0,0,1,2---
   
  

  

   
  

  
 back_insert_iterator<list<int> > itBack = back_inserter(vecDest);//这里也可以直接调用构造函数
   
  

  
 *itBack = 101;
   
  

  
 *itBack = 102;//itBack每次都指向容器最后的元素
   
  

  
 PrintElements(vecDest);//.....101,102
   
  

  

   
  

  
 front_insert_iterator<list<int> > itFront = front_insert_iterator<list<int> >(vecDest);
   
  

  
 *itFront = 1001;
   
  

  
 *itFront = 1002;
   
  

  
 PrintElements(vecDest);//1002,1001......
   
  

  

   
  

  
 insert_iterator<list<int> > itIst = inserter(vecDest, vecDest.begin());
   
  

  
 *itIst = 11;
   
  

  
 *itIst = 12;
   
  

  
 PrintElements(vecDest);//--11,12,1002,1001.....
   
  

  
 // *itIst = value;相当于
   
  

  
 // itIst = c.insert(it,value);
   
  

  
 // ++itIst;
   
  

  
 // insert函数返回的是指向插入元素的迭代器，由于该函数是在给定迭代器之前插入元素，所以++itIst之后
   
  

  
 // itIst依然指向的是原来的元素。操作结束后itIst指向的位置未发生改变
   
  

  

   
  

  
 return 0;
   
  

  
}
  
 

From for notes (Wiz)

C + + Insert iterator