The parameter for the constructor with 1 parameter date2016(int dd) ranges from 1
to 365 (the code should report error and exit if the parameter is not in the range)
and is day of year for the date in 2016. The constructor converts day of year to
month and day of month. For example the 70th day of the year is March 11: the
constructor should make m =3 and d = 11 when date2016(70) is invoked.