std::back_inserter

 

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定义在头文件 <iterator> 中
template< class Container > std::back_insert_iterator<Container> back_inserter( Container& c );		(自 C++20 起为 constexpr)

back_inserter 是一个方便的函数模板，它为容器 c 构造一个 std::back_insert_iterator，类型从参数的类型推断得出。

参数

c

-

支持 push_back 操作的容器

返回值

一个 std::back_insert_iterator，可用于将元素添加到容器 c 的末尾。

可能的实现

template<class Container> std::back_insert_iterator<Container> back_inserter(Container& c) { return std::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

参见

back_insert_iterator	用于在容器末尾插入的迭代器适配器 (类模板)
front_inserter	创建 std::front_insert_iterator，类型从参数推断得出 (函数模板)
inserter	创建 std::insert_iterator，类型从参数推断得出 (函数模板)