#include <iostream> #include <iomanip> using namespace std; class Date{ public: Date(int year,int month=1,int day=1) { _year=year; _month=month; _day=day; } int GetMonthDay() { int monthdays[13]={0,31,28,31,30,31,30,31,31,30,31,30,31}; if((_year%4==0&&_year%100!=0)||_year%400==0)...