把二元查找树转变成排序的双向链表

 

把二元查找树转变成排序的双向链表

#include <stdio.h>

#include <iostream.h>

struct BSTreeNode

{

int m_nValue; // value of node

BSTreeNode *m_pLeft;// left child of node

BSTreeNode *m_pRight; // right child of node

};

typedef BSTreeNode DoubleList;

DoubleList *pHead;

DoubleList *pListIndex;

void convertToDoubleList(BSTreeNode* pCurrent);

// 创建二元查找树

void addBSTreeNode(BSTreeNode* &pCurrent, int value)

{

if (NULL == pCurrent)

{

BSTreeNode * pBSTree = new BSTreeNode();

pBSTree->m_pLeft = NULL;

pBSTree->m_pRight = NULL;

pBSTree->m_nValue = value;

pCurrent = pBSTree;

 

}

else

{

        if ((pCurrent->m_nValue) > value)

{

addBSTreeNode(pCurrent->m_pLeft, value);

}

else if ((pCurrent->m_nValue) < value)

{

addBSTreeNode(pCurrent->m_pRight, value);

}

else

{

// cout<<"重复加入节点"<<endl;

}

}

}

// 遍历二元查找树 中序

void ergodicBSTree(BSTreeNode *pCurrent)

{

if (NULL == pCurrent)

{

return;

}

if (NULL != pCurrent->m_pLeft)

{

ergodicBSTree(pCurrent->m_pLeft);

}

// 节点接到链表尾部

convertToDoubleList(pCurrent);

// 右子树为空

if (NULL != pCurrent->m_pRight)

{

ergodicBSTree(pCurrent->m_pRight);

}

}

// 二叉树转换成 list

void convertToDoubleList(BSTreeNode *pCurrent)

{

pCurrent->m_pLeft = pListIndex;

if (NULL != pListIndex)

{

pListIndex->m_pRight = pCurrent;

}

else

{

pHead = pCurrent;

}

pListIndex = pCurrent;

cout<<pCurrent->m_nValue<<endl;

}

int main()

{

BSTreeNode *pRoot = NULL;

pListIndex = NULL;

pHead = NULL;

addBSTreeNode(pRoot, 10);

addBSTreeNode(pRoot, 4);

addBSTreeNode(pRoot, 6);

addBSTreeNode(pRoot, 8);

addBSTreeNode(pRoot, 12);

addBSTreeNode(pRoot, 14);

addBSTreeNode(pRoot, 15);

addBSTreeNode(pRoot, 16);

ergodicBSTree(pRoot);

return 0;

}