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std::vector::push_back

From cppreference.com
< cpp‎ | container‎ | vector
void push_back( const T& value );
(1)
void push_back( T&& value );
(2) (since C++11)

Appends the given element value to the end of the container.

1) The new element is initialized as a copy of value.
2) value is moved into the new element.

If the new size() is greater than capacity() then all iterators and references (including the past-the-end iterator) are invalidated. Otherwise only the past-the-end iterator is invalidated.

Contents

[edit] Parameters

value - the value of the element to append
Type requirements
-
T must meet the requirements of CopyInsertable in order to use overload (1).
-
T must meet the requirements of MoveInsertable in order to use overload (2).

[edit] Return value

(none)

[edit] Complexity

Amortized constant.

[edit] Exceptions

If an exception is thrown, this function has no effect (strong exception guarantee).

If T's move constructor is not noexcept and T is not CopyInsertable into *this, vector will use the throwing move constructor. If it throws, the guarantee is waived and the effects are unspecified. (since C++11)

[edit] Example

#include <vector>
#include <iostream>
#include <iomanip>
 
int main()
{
    std::vector<std::string> numbers;
 
    numbers.push_back("abc");
    std::string s = "def";
    numbers.push_back(std::move(s));
 
    std::cout << "vector holds: ";
    for (auto&& i : numbers) std::cout << std::quoted(i) << ' ';
    std::cout << "\nMoved-from string holds " << std::quoted(s) << '\n';
}

Output:

vector holds: "abc" "def" 
Moved-from string holds ""

[edit] See also

constructs an element in-place at the end
(public member function) [edit]
removes the last element
(public member function) [edit]