第3题

#include<iostream>using namespace std;class Data{public:Data(int =1,int =1,int =2005);void display();private:int month;int day;int year;};Data::Data(int m,int d,int y):month(m),day(d),year(y){}void Data::display(){cout<<month<<"/"<<day<<"/"<<year<<endl;}int main(){Data d1(10,13,2005);Data d2(12,30);Data d3(10);Data d4;d1.display(); d2.display();d3.display();d4.display();return 0;}

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