C++程序设计原理与实践__记录1

#include<iostream>#include<string>using namespace std;class Year{public:Year(int x):y(x){if(x<Min||x>Max) cout<<"inittal error!!!"<<endl;}Year(){};int year(){return y;}private:int y;    static const int Min;static const int Max;};const int Year::Max=2200;const int Year::Min=1800;class Date{public:enum Month{jan=1,feb,mar,apr,may,jun,jul,aug,sep,oct,nov,dec};Date(Year yy,Month mm,int dd):y(yy),m(mm),d(dd){}Date():y(default_date().year()),m(default_date().month()),d(default_date().day()){}    Year year(){return y;}Month month(){return m;}int day(){return d;}private:Year y;Month m;int d;Date &default_date(){static Date dd(Year(2011),Date::jan,1);return dd;}};int main(){Date d1(Year(2010),Date::mar,23);Date d2;return 0;}