leapyear (int year)
leapyear (long int year)
leapyear (int year){  /* Don't add YEAR to TM_YEAR_BASE, as that might overflow.     Also, work even if YEAR is negative.  */  return    ((year & 3) == 0     && (year % 100 != 0	 || ((year / 100) & 3) == (- (TM_YEAR_BASE / 100) & 3)));}