C++将二叉树转为双向链表及判断两个链表是否相交

4=6=8=10=12=14=16

struct BSTreeNode
{
int m_nValue; // value of node
BSTreeNode *m_pLeft; // left child of node
BSTreeNode *m_pRight; // right child of node
};

void convertToDoubleList(BSTreeNode* pCurrent)
{
  pCurrent->m_pLeft=pIndex;
  if (pIndex == NULL)
  {
    pHead=pCurrent;
  }
  else
  {
    pIndex->m_pRight=pCurrent;
  }
  pIndex=pCurrent;
}

typedef struct node
{
  int data;
  struct node * next;
}List;

int isJoinedNocylic(List * h1,List * h2)
{
  while(h1 != NULL)
    h1 = h1->next;
  while(h2 != NULL)
    h2 = h2->next;
   
  return h1 == h2;
}

int isCycle(List * h)
{
  List * p1, * p2;
  p1 = p2 = h;
  int flag;
   
  while(p2 != NULL && p2->next != NULL)
  {
    p1 = p1->next;
    p2 = p2->next->next;
    if(p1 == p2)
    {  
      flag = 1;
      break;
    }
  }
   
  flag = 0; 
  return flag;
}

2s = s + nr
s= nr

a + x = nr
a + x = (n – 1)r +r = (n-1)r + L - a
a = (n-1)r + (L – a – x)

List * isJoined(List * h1,List * h2)
{
  List * ph1,*p1,*p2;
  int flag;
 
  ph1 = h1; 
  while(ph1->next != NULL)
    ph1 = ph1->next;  
  ph1->next = h2;
 
  if(0 == isCycle(h1))
  {
    flag = 0;
  }
  else
  {
    p1 = h1;
    while(p1 != p2)
    {
      p1 = p1->next;
      p2 = p2->next;
    }
    flag = p1;
  }
   
  return flag;
}