【STL】back_inserter与back_insert_iterator

back_inserter一个成员函数，返回值是back_insert_iterator, 本质上是push_back进行操作的, 返回值back_insert_iterator, 并实现其自增.

std::vector<int> firstvector, secondvector;for (int i=1; i<=5; i++){ firstvector.push_back(i); secondvector.push_back(i*10);}// 在firstvector向量后面加入secondvector的值.std::copy(secondvector.begin(), secondvector.end(), std::back_inserter(firstvector));std::vector<int>::iterator it;for ( it = firstvector.begin(); it!= firstvector.end(); ++it )std::cout << *it << " ";std::cout << std::endl;

下面是一个back_insert_iterator的例子

std::vector<int> vec;for (int i = 0 ; i < 3; ++i)vec.push_back(i);std::vector <int>::iterator vIter;std::cout << "The initial vector vec is: ( ";for (vIter = vec.begin(); vIter != vec.end(); vIter++)std::cout << *vIter << " ";std::cout << ")." << std::endl;// Insertions can be done with template functionstd::back_insert_iterator<std::vector<int> > backiter(vec);*backiter = 30;backiter++;*backiter = 40;// Alternatively, insertions can be done with the// back_insert_iterator member functionstd::back_inserter(vec) = 500;std::back_inserter(vec) = 600;std::cout << "After the insertions, the vector vec is: ( ";for (vIter = vec.begin(); vIter != vec.end(); vIter++)std::cout << *vIter << " ";std::cout << ")." << std::endl;