Circular queue implemented in array.
(Corrected error in print() )

Always keep one node empty.
head points to first element in queue.
tail points to location where next element is to be inserted

NOTE ALL ADDITION (including ++) is % size
/* initialize queue pointers */
head = tail = 0;

/* test for full */
return head == tail + 1;

/* test for empty */
return head == tail;

/* insert x at tail */
if ( !full) 
	q[tail++] = x;
	
/* delete from head */
if ( !empty)
	return q[head++];
	
/* print from head to tail */
/* note, this is not really a queue operation, but is handy for debugging */
if (!empty)
	for (n = head; n != tail-1; n ++) // n = head; n != tail - 1; n++
		print q[n];