二叉搜索樹轉化爲有序雙向鏈表

#include<iostream>
using namespace std;

struct BinaryTreeNode{
	int m_value;
	BinaryTreeNode* m_left;
	BinaryTreeNode* m_right;
};

BinaryTreeNode* Convert(BinaryTreeNode* pRootoftree){
	BinaryTreeNode *pLastNodeInList = NULL;
	ConvertNode(pRootoftree,&pLastNodeInList);
	
	//pLastNodeList指向雙向離岸邊的尾節點
	//我們需要返回頭結點
	 BinaryTreeNode *pHeadoflist = pLastNodeInList;
	 while(pHeadoflist != NULL && pHeadoflist->m_left != NULL)
	  	pHeadoflist = pHeadoflist->m_left;
	  	
	 return pHeadoflist;
}

void ConvertNode(BinaryTreeNode* pNode,BinaryTreeNode* pRootoftree** pLastNodeinlist){
	if(pNode == NULL) return ;
	BinaryTreeNode *pCurrent = pNode;
	
	if(pCurrent->m_left != NULL)
	ConvertNode(pCurrent->m_left,pLastNodeinlist);
	
	pCurrent->m_left = *pLastNodeinlist;
	if(*pLastNodeinlist != NULL)
	(*pLastNodeinlist)->m_right = pCurrent;
	
	*pLastNodeinlist = pCurrent;
	
	if(pCurrent->m_right!=NULL)
	ConvertNode(pCurrent->m_right,pLastNodeinlist);
}