public boolean push(E node) {
		if (node == null)
			return false;
		Node<E> hcr = head;
		while (hcr.next != null) {
			if (hcr.next.val.compareTo(node) >= 0) {
				break;
			}
			hcr = hcr.next;
		}
		Node<E> tem = new Node<E>(node, hcr.next);
		hcr.next = tem;
		++size;
		return true;
	}