resource ArrayQueue
	extend Queue
body ArrayQueue(int size)
	int store[0:size-1]
	int  front = 0; int rear = 0; int count = 0
	proc insert(item)  {
		if (count < size) {
			store[rear] = item
			rear = (rear+1)%size
			count++
		} else {
			write("overflow")
		}
	}
	proc remove() returns item  {
		if (count > 0) {
			item = store[front]
			front = (front+1)%size
			count--
		} else {
			write("underflow")
		}
	}
end ArrayQueue