//CC150 2.3
	//by dnalwqer 03/20/2015
	//idea: just copy the next node to the current node and delete the next one.
	//note: if the node is the last node in the linked list, it can not be successful. Please remember.

	public void deleteMiddle(Node node) {
		if (node == null || node.next == null) {
			return ;
		}
		Node n = node;
		n.val = n.next.val;
		n.next = n.next.next;
	}