Binary Tree Upside Down

Given a binary tree where all the right nodes are either leaf nodes 
with a sibling (a left node that shares the same parent node) or empty, 
flip it upside down and turn it into a tree where the original right nodes 
turned into left leaf nodes. Return the new root.

For example:
Given a binary tree {1,2,3,4,5},
　　1
　  / \
　 2  3
   / \
  4  5
return the root of the binary tree [4,5,2,#,#,3,1].
　  4
　 / \
   5  2
  / \
 3  1

题内容是根据题目网上搜到的没法OJ，所以不知道自己的代码是否正确

class Solution {
public:
    TreeNode *upsideDownBinaryTree(TreeNode *root) 
    {
    	TreeNode *par = 0, *nodeR = 0, *cur = root;
    	while (cur != 0)
    	{
    		TreeNode *nextL = cur->left, *nextR = cur->right;
    		cur->left = nodeR;
    		cur->right = par;
    		par = cur;
    		nodeR = nextR;
    		if (nextL == 0)
    			return cur;
    		cur = nextL;    
    	}
    	return cur;
    }
};