劍指offer-二叉搜索樹與雙向鏈表-python

題目描述

輸入一棵二叉搜索樹，將該二叉搜索樹轉換成一個排序的雙向鏈表。要求不能創建任何新的結點，只能調整樹中結點指針的指向。、

# -*- coding:utf-8 -*-
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None
class Solution:
    def __init__(self):
        self.listHead = None
        self.listTail = None
    def Convert(self, pRootOfTree):
        if pRootOfTree==None:
            return
        #中續遍歷
        self.Convert(pRootOfTree.left)
        if self.listHead==None:
            self.listHead = pRootOfTree
            self.listTail = pRootOfTree
        else:
            #22行與24行主要是增加雙向連接
            #22行指向listTail.right
            self.listTail.right = pRootOfTree
            #24行指回去
            pRootOfTree.left = self.listTail
            #移動到下一個位置
            self.listTail = pRootOfTree
        self.Convert(pRootOfTree.right)
        return self.listHead