剑指offer_1

class {
public:
  CMyString(char* pData=NULL);
  CMyString(const CMyString& str);
  ~CMyString(void);
private:
  char* m_pData;

}

CMyString& CMyString::operator=(const CMyString &str){
  if(this==&str)
      return *this;
  delete []m_pData;
  m_pData=NULL;
  m_pData=new char[strlen(str.m_pData)+1];
  strcpy(m_pData,str.m_pData);
  return *this;    
}

CMyString& CMyString::operator=(const CMyString &str) {

	if (this!- &str) {
		CMyString strTemp(str);
		char* pTemp = strTemp.m_pData;
		m_pData = pTemp;
	}
	return *this;
}