C++

Reference

<deque>

deque

public member function
<deque>

std::deque::push_back

void push_back (const value_type& val);
void push_back (const value_type& val);void push_back (value_type&& val);
Add element at the end
Adds a new element at the end of the deque container, after its current last element. The content of val is copied (or moved) to the new element.

This effectively increases the container size by one.

Parameters

val
Value to be copied (or moved) to the new element.
Member type value_type is the type of the elements in the container, defined in deque as an alias of its first template parameter (T).

Return value

none

The storage for the new elements is allocated using the container's allocator, which may throw exceptions on failure (for the default allocator, bad_alloc is thrown if the allocation request does not succeed).

Example

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// deque::push_back
#include <iostream>
#include <deque>

int main ()
{
  std::deque<int> mydeque;
  int myint;

  std::cout << "Please enter some integers (enter 0 to end):\n";

  do {
    std::cin >> myint;
    mydeque.push_back (myint);
  } while (myint);

  std::cout << "mydeque stores " << (int) mydeque.size() << " numbers.\n";

  return 0;
}
The example uses push_back to add a new element to the container each time a new integer is read.

Complexity

Constant.

Iterator validity

All iterators related to this container are invalidated. Pointers and references to elements in the container remain valid, referring to the same elements they were referring to before the call.

Data races

The container is modified.
No existing elements are accessed (although see iterator validity above).

Exception safety

Strong guarantee: if an exception is thrown, there are no changes in the container.
If allocator_traits::construct is not supported with val as argument, it causes undefined behavior.

See also

deque::push_front
Insert element at beginning (public member function)
deque::pop_back
Delete last element (public member function)
deque::insert
Insert elements (public member function)