C / C++ / MFC

class CYourClass
{
public:
   COleDateTime ChangedDates[2];
....
};

void CYourClass::AssignValues()
{
   ChangedDates[0] = date1;
   ChangedDates[1] = date2;
}

// use from CYourClass member:
int CYourClass::CalcDifference(period dt)
{
   int iDifference = 0;
   // calculate the number of dt intervals
   // this code won't work as written, it's just as an example 
   COleDateTime date = ChangedDates[0];
   for (int i=0; ChangedDates[1]>date; i++) {
      iDifference++;
      date += dt;
   }
   // now return the number of dt periods
   return iDifference;
}
// use ChangedDates from outside CYourClass:
int CSomeOtherClass::CalcDifference(CYourClass yourclass, period dt)
{
   int iDifference = 0;
   // calculate the number of dt intervals
   // this code won't work as written, it's just as an example
   COleDateTime date = yourclass.ChangedDates[0];
   for (int i=0; yourclass.ChangedDates[1]>date; i++) {
      iDifference++;
      date += dt;
   }
   // now return the number of dt periods
   return iDifference;
}

COleDateTime[] CMyClass::ModifyDates(COleDateTime date1, COleDateTime date2)
{
   ChangedDates[0] = date1;
   ChangedDates[1] = date2;
   return ChangedDates;
}

int CMyClass::CalcNumberOfPeriod(COleDateTime StartDate,COleDateTime EndDate)
{
   int iNumberOfPeriod;
   ModifyDates(StartDate,EndDate); // you actually don't need ModifyDates to return the array
   //calculate the difference using ChangedDates[0] and ChangedDates[1] - they will now contain your StartDate and EndDate.
.
.
.
return iNumberOfPeriod;
}

void CMyClass::ModifyDates(COleDateTime* pDates)
{
   // pDates points to an array of two dates, pDates[0] and pDates[1]
   // do whatever modification is needed.
}

int CMyClass::CalcNumberOfPeriod(COleDateTime StartDate COleDateTime EndDate, periodtype dt)
{
   COleDateTime Dates[2];
   Dates[0] = StartDate;
   Dates[1] = EndDate;
   ModifyDates(Dates); // Dates i type COleDateTime*. Dates[0] and Dates[1] is type COleDateTime
   int iPeriods;
   // calculate the number of periods between the dates
   iPeriods = .....
   return iPeriods;
}

COleDateTime* CMyClass::AllocAndModifyDates(COleDateTime date1, COleDateTime date2)
{
   COleDateTime* pDates = new COleDateTime[2];
   pDates[0] = date1;
   pDatse[1] = date2;
   // do the modification
   return pDates;
}

int CMyClass::CalcNumberOfPeriod(COleDateTime StartDate, COleDateTime EndDate, periodtype dt)
{
   COleDateTime* pDates = AllocAndModifyDates(StartDate, EndDate);
   int iPeriods;
   // do the calculation of number of periods
   // now we're done using the dates, let's delete them
   delete[] pDates;
   return iPeriods;
}

delete[] Date;

while(i<10)
{
   while(j<10) // gets called for each instance of i
   {

   }
}

CArchive& operator <<(CArchive & ar, const CObject* pOb);
void CArchive::WriteObject(const CObject* pOb);