vector::front


public member function
      reference front ( );
const_reference front ( ) const;

Access first element

Returns a reference to the first element in the vector container.

Unlike member vector::begin, which returns an iterator to this same element, this function returns a direct reference.

Parameters

none

Return value

A reference to the first element in the vector.

Member types reference and const_reference are the reference types to the elements of the vector container (for the default storage allocation model, allocator, these are T& and const T& respectively).

Example

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// vector::front
#include <iostream>
#include <vector>
using namespace std;

int main ()
{
  vector<int> myvector;

  myvector.push_back(77);
  myvector.push_back(16);

  // now front equals 77, and back 16

  myvector.front() -= myvector.back();

  cout << "myvector.front() is now " << myvector.front() << endl;

  return 0;
}


Output:
myvector.front() is now 61


Complexity

Constant.

See also

vector::at Access element (public member function)
vector::operator[] Access element (public member function)
vector::back Access last element (public member function)