二叉搜索树 转 有序双向链表

/*    27:> 二叉搜索树 转 有序双向链表    左孩子指向前驱，右孩子指向后继    递归，动态规划*/BinTree* First(BinTree* pRoot){    if (pRoot == NULL)        return NULL;    BinTree* pF = pRoot;    while (pF->m_pLeft)    {        pF = pF->m_pLeft;    }    return pF;}BinTree* Last(BinTree* pRoot){    if (pRoot == NULL)        return NULL;    BinTree* pL = pRoot;    while (pL->m_pRight)    {        pL = pL->m_pRight;    }    return pL;}void Convert(BinTree*& pRoot){    if (pRoot == NULL)        return;    BinTree*pL = pRoot->m_pLeft;    BinTree*pR = pRoot->m_pRight;    if (pL && pL->m_pRight != pRoot)    {        pRoot->m_pLeft = Last(pL);        pRoot->m_pLeft->m_pRight = pRoot;        Convert(pL);    }    if (pR && pR->m_pLeft != pRoot)    {        pRoot->m_pRight = First(pR);        pRoot->m_pRight->m_pLeft = pRoot;        Convert(pR);    }}