Reference
C Library
IOstream Library
Strings library
STL Containers
STL Algorithms
Miscellaneous
STL Containers
bitset
deque
list
map
multimap
multiset
priority_queue
queue
set
stack
vector
vector
comparison operators
vector::vector
vector::~vector
member functions:
vector::assign
vector::at
vector::back
vector::begin
vector::capacity
vector::clear
vector::empty
vector::end
vector::erase
vector::front
vector::get_allocator
vector::insert
vector::max_size
vector::operator=
vector::operator[]
vector::pop_back
vector::push_back
vector::rbegin
vector::rend
vector::reserve
vector::resize
vector::size
vector::swap


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(78);
  myvector.push_back(16);
  // now front equals 78, and back 16
  myvector.front() -= myvector.back();
  cout << "myvector.front() is now " << myvector.front() << endl;
  return 0;
}


Output:
myvector.front() is now 62

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)