Returns a reference to the first element in a deque.
reference front( );
const_reference front( ) const;
Return Value
If the deque is empty, the return is undefined.
Remarks
If the return value of front is assigned to a const_reference, the deque object cannot be modified. If the return value of front is assigned to a reference, the deque object can be modified.
When compiling with _SECURE_SCL 1, a runtime error will occur if you attempt to access an element in an empty deque. See Checked Iterators for more information.
Example
// deque_front.cpp
// compile with: /EHsc
#include <deque>
#include <iostream>
int main( )
{
using namespace std;
deque <int> c1;
c1.push_back( 10 );
c1.push_back( 11 );
int& i = c1.front( );
const int& ii = c1.front( );
cout << "The first integer of c1 is " << i << endl;
i++;
cout << "The second integer of c1 is " << ii << endl;
}
The first integer of c1 is 10 The second integer of c1 is 11
Requirements
Header: <deque>
Namespace: std