std::back_inserter

 

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在标头 <iterator> 定义
template<class Container > std::back_insert_iterator<Container> back_inserter( Container& c );		(C++20 起为 constexpr)

back_inserter 是便利函数模板，为容器 c 构造 std::back_insert_iterator，并拥有从实参类型推导的类型。

参数

c

-

支持 push_back 操作的容器

返回值

能用于向容器 c 尾端添加元素的 std::back_insert_iterator。

可能的实现

template<class Container>std::back_insert_iterator<Container> back_inserter(Container& c){returnstd::back_insert_iterator<Container>(c);}

示例

运行此代码

#include <algorithm>#include <iostream>#include <iterator>#include <vector>   int main(){std::vector<int> v{1, 2, 3, 4, 5, 6, 7, 8, 9, 10};std::fill_n(std::back_inserter(v), 3, -1);for(int n : v)std::cout<< n <<' ';std::cout<<'\n';}

输出：

1 2 3 4 5 6 7 8 9 10 -1 -1 -1

参阅

back_insert_iterator	在容器尾部插入的迭代器适配器 (类模板)
front_inserter	创建拥有从实参推出的类型的 std::front_insert_iterator (函数模板)
inserter	创建拥有从实参推出的类型的 std::insert_iterator (函数模板)