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empty.java

        public E peek () throws EmptyStackException {
		if (empty())
			throw new EmptyStackException();
		return stack[top];
	}
	
	public E pop () throws EmptyStackException {
		if (empty())
			throw new EmptyStackException();
		E element = stack[top];
		stack[top--] = null;
		return element;
	}
 
        public boolean empty () {
		try  {
			peek();
		} catch (EmptyStackException e) {
			return true;
		} else {
			return false;
		}
        }