二元查找树转变成排序的双向链表（树）

 /*
    Name: 二元查找树转变成排序的双向链表（树）
    Copyright: 
    Author: yifi
    Date: 23/11/16 17:06
    Description: 
*/


#include <iostream>
using namespace std;

typedef struct _BSTreeNode{
    int m_Value;
    _BSTreeNode* pLeft;
    _BSTreeNode* pRight;
}BSTreeNode,*pBSTreeNode; 

void addBSTreeNode(BSTreeNode *&pCurrent,int value);
void inOrderBSTree(BSTreeNode* pBSTree);
void convertToDoubleList(BSTreeNode* pCurrent);

BSTreeNode *pHead=NULL;//指向循环队列头结点
BSTreeNode *pIndex=NULL;//指向前一个结点
int main()
{
    BSTreeNode *pRoot=NULL;
    addBSTreeNode(pRoot,10);
    addBSTreeNode(pRoot,6);
    addBSTreeNode(pRoot,14);
    addBSTreeNode(pRoot,4);
    addBSTreeNode(pRoot,8);
    addBSTreeNode(pRoot,12);
    addBSTreeNode(pRoot,16);
    inOrderBSTree(pRoot);
    return 0;
}


void addBSTreeNode(BSTreeNode *&pCurrent,int value)
{
    if (pCurrent == NULL)     
    {
        BSTreeNode* pTemp = new BSTreeNode();
        pTemp->m_Value = value;
        pTemp->pLeft = NULL;
        pTemp->pRight = NULL;
        pCurrent = pTemp;
    }
    else if (pCurrent->m_Value < value)
    {
        addBSTreeNode(pCurrent->pRight,value);
    }
    else if (pCurrent->m_Value > value)
    {
        addBSTreeNode(pCurrent->pLeft,value);
    }
    else 
    {
        cout << "Node Repeated" << endl;
    }
}

void inOrderBSTree(BSTreeNode* pBSTree)
{
    if (pBSTree == NULL)
    {
        return ;
    }
    if (pBSTree->pLeft != NULL)
    {
        inOrderBSTree(pBSTree->pLeft);
    }
     convertToDoubleList(pBSTree);
    if (pBSTree->pRight != NULL)
    {
        inOrderBSTree(pBSTree->pRight);
    }
     
}
void convertToDoubleList(BSTreeNode* pCurrent)
{
    pCurrent->pLeft = pIndex;
    if (pIndex == NULL)
    {
        pHead = pCurrent;
    }
    else 
    {
        pIndex->pRight = pCurrent;
    }
    pIndex = pCurrent;
    
    cout << pCurrent->m_Value << " "; 
}