public void insert(int k, Item item)
	{
		// associate element with an index k by inserting it into items[k]
		items[k] = item;

		// insert item index, k, into the priority queue
		N++;
		pq[N] = k; // insert into last position
		qp[k] = N; // reverse index
		swim(N); // make it swim up to its rightful place. The reverse index is
					// also adjusted
	}