# -*- coding:utf-8 -*-
# class TreeLinkNode:
# def __init__(self, x):
# self.val = x
# self.left = None
# self.right = None
# self.next = None
class Solution:
def GetNext(self, pNode):
# write code here
if not pNode:
return None
if pNode.right:
cur=pNode.right
while cur:
if cur.left:
cur=cur.left
else:
return cur
else:
cur=pNode
while cur.next and cur.next.left!=cur:
cur=cur.next
return cur.next