deque::front

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

See Also

Reference

deque Class

deque::front and deque::back

Standard Template Library

Other Resources

deque Class Members