DWORD ClndrDayNum(WORD vY, WORD vM, WORD vD)
{
WORD a = ((14-vM)/12);
WORD y = (vY + 4800 - a);
WORD m = (vM + 12*a - 3);
DWORD d = vD + ((153*m + 2)/5) + 365*y + (y/4) - (y/100) + (y/400) - 32045;
return(d-startdata);
}

void ClndrDate(DWORD DNum, WORD *vY, WORD *vM, WORD *vD)
{
DWORDs a = (DNum+startdata) + 32044;
DWORDs b = (4*a + 3)/146097;
DWORDs c = a-((146097*b)/4);
DWORDs d = (4*c + 3)/1461;
DWORDs e = c - (1461*d)/4;
DWORDs m = (5*e + 2)/153;
*vD = (e - ((153*m + 2)/5) + 1);
*vM = (m + 3 - 12 * (m/10));
*vY = (100*b + d - 4800 + (m/10));
}