queue::queue
Constructs a queue that is empty or that is a copy of a base container object.
queue( );
explicit queue(
const container_type& _Right
);
Parameters
- _Right
The const container of which the constructed queue is to be a copy.
Remarks
The default base container for queue is deque. You can also specify list as a base container, but you cannot specify vector, because it lacks the required pop_front member function.
Example
// queue_queue.cpp
// compile with: /EHsc
#include <queue>
#include <vector>
#include <list>
#include <iostream>
int main( )
{
using namespace std;
// Declares queue with default deque base container
queue <char> q1;
// Explicitly declares a queue with deque base container
queue <char, deque<char> > q2;
// These lines don't cause an error, even though they
// declares a queue with a vector base container
queue <int, vector<int> > q3;
q3.push( 10 );
// but the following would cause an error because vector has
// no pop_front member function
// q3.pop( );
// Declares a queue with list base container
queue <int, list<int> > q4;
// The second member function copies elements from a container
list<int> li1;
li1.push_back( 1 );
li1.push_back( 2 );
queue <int, list<int> > q5( li1 );
cout << "The element at the front of queue q5 is "
<< q5.front( ) << "." << endl;
cout << "The element at the back of queue q5 is "
<< q5.back( ) << "." << endl;
}
The element at the front of queue q5 is 1. The element at the back of queue q5 is 2.
Requirements
Header: <queue>
Namespace: std