std::back_inserter

 

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Defined in header <iterator>
template<class Container > std::back_insert_iterator<Container> back_inserter( Container& c );		(constexpr since C++20)

back_inserter is a convenience function template that constructs a std::back_insert_iterator for the container c with the type deduced from the type of the argument.

Parameters

c

-

container that supports a push_back operation

Return value

A std::back_insert_iterator which can be used to add elements to the end of the container c.

Possible implementation

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

Example

Run this code

#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';}

Output:

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

See also

back_insert_iterator	iterator adaptor for insertion at the end of a container (class template)
front_inserter	creates a std::front_insert_iterator of type inferred from the argument (function template)
inserter	creates a std::insert_iterator of type inferred from the argument (function template)