std::copy() & std::back_inserter()

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std::copy

template<class InputIterator, class OutputIterator>  OutputIterator copy (InputIterator first, InputIterator last, OutputIterator result){  while (first!=last) {    *result = *first;    ++result; ++first;  }  return result;}

std::copy()函数和strcpy()的实现类似,只是参数类型由char 变为 iterator

// copy algorithm example#include <iostream>     // std::cout#include <algorithm>    // std::copy#include <vector>       // std::vectorint main () {  int myints[]={10,20,30,40,50,60,70};  std::vector<int> myvector (7);//一定要初始化大小  //这三个参数要记住  std::copy ( myints, myints+7, myvector.begin() );  //参数       first   last      result      // [first,last)  std::cout << "myvector contains:";  for (std::vector<int>::iterator it = myvector.begin(); it!=myvector.end(); ++it)    std::cout << ' ' << *it;  std::cout << '\n';  return 0;}

Output:myvector contains: 10 20 30 40 50 60 70

std::back_inserter()

// back_inserter example#include <iostream>     // std::cout#include <iterator>     // std::back_inserter#include <vector>       // std::vector#include <algorithm>    // std::copyint main () {  std::vector<int> foo,bar;  for (int i=1; i<=5; i++)  { foo.push_back(i); bar.push_back(i*10); }  std::copy (bar.begin(),bar.end(),back_inserter(foo));//back_inserter() 把当前iterator插入到foo容器尾部，返回类型是一个叫back_insert_iterator的东西..  std::cout << "foo contains:";  for ( std::vector<int>::iterator it = foo.begin(); it!= foo.end(); ++it )      std::cout << ' ' << *it;  std::cout << '\n';  return 0;}

Output:foo contains: 1 2 3 4 5 10 20 30 40 50

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