#include<iostream> using namespace std; class Date { public: Date(int year = 1900, int month = 1, int day = 1)//类的初始化 :_year(year) , _month(month) , _day(day) { if (!IsInvalidDate()) { _year = 1900; _month = 1; _day = 1; } } Date operator+(int days)//实现日期的+操作 { if ...