// Code derived from Stroustrup's PPP2 book// § 9.7.3 Default constructors// -and beginning on p 328enumclassMonth{jan=1,feb,mar,apr,may,jun,jul,aug,sep,oct,nov,dec};//------------------------------------------------------------------------------// let’s provide [a default constructor] (just to show we can)classDate{public:Date();// default constructor// . . .intyear(){returny;}Monthmonth(){returnm;}intday(){returnd;}private:inty;Monthm;intd;};// We have to pick a default date. The first day of the 21st century might be a// reasonable choiceDate::Date():y{2001},m{Month::jan},d{1}{}//------------------------------------------------------------------------------intmain(){}