public IntArrayBag clone()
	{//create a clone of an IntArrayBag object
		IntArrayBag answer; // another object named answer???
		
		try
		{
			answer = (IntArrayBag) super.clone();
		}
		catch(CloneNotSupportedException ex)
		{//it would not occur, but if it does, programming error,check not to forget "implements Cloneable"
			throw new RuntimeException ("this class does not implement Cloneable");
		}
		answer.data = data.clone();
		return answer;
	}