deque::begin


public member function
      iterator begin ();
const_iterator begin () const;

Return iterator to beginning

Returns an iterator referring to the first element in the container.

Notice that unlike member deque::front, which returns a reference to the first element, this function returns a random access iterator.

Parameters

none

Return Value

An iterator to the beginning of the sequence.

Both iterator and const_iterator are member types. In the deque class template, these are random access iterators.

Example

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// deque::begin
#include <iostream>
#include <deque>
using namespace std;

int main ()
{
  deque<int> mydeque;
  deque<int>::iterator it;

  for (int i=1; i<=5; i++) mydeque.push_back(i);

  cout << "mydeque contains:";

  it = mydeque.begin();

  while (it != mydeque.end())
    cout << " " << *it++;

  cout << endl;

  return 0;
}


Output:
mydeque contains: 1 2 3 4 5


Complexity

Constant.

See also

deque::front Access first element (public member function)
deque::end Return iterator to end (public member function)
deque::rbegin Return reverse iterator to reverse beginning (public member function)
deque::rend Return reverse iterator to reverse end (public member function)