Number of elements in queue is: 7
    front is 8 back is 9
    front is 9 back is 9
    front is 3 back is 9
    front is 3 back is 9
    front is 8 back is 9
    front is 4 back is 9
    front is 9 back is 9



    #include <iostream>
    #include <queue>
    using namespace std;
    
    // empty(): Checks to see if the stack is empty.
    
    // pop():   Deletes the element from the front of the queue.
    
    // push():  Adds element to the back of the queue.
    
    // size():  Computes and returns the number of elements in the queue.
    
    // back():  Returns a reference to the last element added to the back of the queue.
    
    // front(): Returns a reference to the first element in the front of the queue.
    
    int main()
    {
        // Queues
    	queue<int> q;
            int f,b;
    
            q.push(8);
            q.push(9);
            q.push(3);
            q.push(3);
            q.push(8);
            q.push(4);
            q.push(9);
            cout << "Number of elements in queue is: " << q.size() << endl;
            while (! q.empty())
             { f = q.front();
               b = q.back();
               cout << "front is " << f << " back is " << b << endl;
               q.pop();
             }
    }