Exercise 1, page 119

Page 119, Exercise 1

Array Queue Implementation: Since all of the work is done in the addq() and deleteq() functions, we only need to print and error message and exit on error or return. Here’s the code with the addq() and deleteq() functions.

 void queue_empty()
{/* check for empty queue is in the deleteq() function */
 fprintf(stderr, “The queue is empty\n”);
}

void queue_full()
{/* code to check for a full queue is in the  addq() function */
   fprintf(stderr, “The queue is Full\n”);
}

void addq(element item)
{/* add an item to the global queue rear points to the current end of the queue */
  if (rear == MAX_QUEUE_SIZE-1)
     queue_full();
  else
     queue[++rear] = item;
}


element deleteq()
{/* remove element at the front of the queue */
     if (front == rear)
	queue_empty();
     else
	return queue[++front];
}