以下程序是用tc3。0编译通过，选择的模式为紧凑模式。
最先开始分配返回的地址，段地址和偏移地址都不为0，但是分配了一些了以后返回的地址都为0，这是为什么呢？！

//////////////////////////
//Header
//CCharList.h


class CCharListNode                      //In Heap....
{
 public:
  char cChar;
  class CCharListNode far *pNext;
  class CCharListNode far *pLast;
};


class CCharList
{
 private:
  CCharListNode far *pList;
  CCharListNode far *pNodeOldLast;
  unsigned int iNodeOldLast;

  CCharListNode far* SeekNodeLast(unsigned int iPosition);

 public:
  unsigned int iListLength;
  CCharList(void);
  ~CCharList(void);
  int CreateList(void);
  int InsertNode(char cChar, unsigned int iPosition);
  int DeleteNode(unsigned int iPosition);
  int DeleteList(void);
  int GetCharFromNode(char &cChar, unsigned int iPosition);
  int SetCharToNode(char cChar, unsigned int iPosition);
};

////////////////////
//cpp file
//CCharList.cpp
#include 
#include 
#include 
#include 
#include 

#define Min(x, y)  xpNext=pList;
 pList->pLast=pList;

 pNodeOldLast=pList;
 iNodeOldLast=0;

 return 1;
}


int CCharList::InsertNode(char cChar, unsigned int iPosition)
{
 if(iPosition>iListLength+1 || iPositionSeekNodeLast(iPosition);

 printf(" [%x:%x] ", FP_SEG(pNode), FP_OFF(pNode));

 pNode->pNext=pSeek->pNext;
 pSeek->pNext=pNode;
 pNode->pLast=pSeek;
 pNode->pNext->pLast=pNode;

 pNode->cChar=cChar;

 iListLength++;

 return 1;
}

int CCharList::DeleteNode(unsigned int iPosition)
{
 if(iPosition>iListLength || iPositionSeekNodeLast(iPosition);

 pNode=pSeek->pNext;
 pSeek->pNext=pNode->pNext;
 pNode->pNext->pLast=pSeek;

 farfree(pNode);

 iListLength--;

 return 1;
}


int CCharList::GetCharFromNode(char &cChar, unsigned int iPosition)
{
 if(iPosition>iListLength || iPositionSeekNodeLast(iPosition);
 cChar=pSeek->pNext->cChar;

 return 1;
}


int CCharList::SetCharToNode(char cChar, unsigned int iPosition)
{
 if(iPosition>iListLength || iPositionSeekNodeLast(iPosition);
 pSeek->pNext->cChar=cChar;

 return 1;
}


int CCharList::DeleteList(void)
{
 int iLimit=iListLength;

 for(unsigned int i=0; iDeleteNode(1);

 farfree(pList);

 return 1;
}


CCharList::~CCharList(void)
{
 DeleteList();
}



CCharListNode far* CCharList::SeekNodeLast(unsigned int iPosition)
{
 iPosition--;

 CCharListNode far *pSeek;
 unsigned int iDistanceFromHead;
 unsigned int iDistanceFromOldLast;
 unsigned int iDistanceTemp;
 unsigned int iDistance;

 iDistanceFromHead=Min(iListLength+1-iPosition, iPosition);
 iDistanceTemp=iNodeOldLast