3.10

#include <iostream>using namespace std;class Date;class Time{public:    Time(int,int,int);    friend void display(const Date &,const Time &);private:    int hour;    int minute;    int sec;};Time::Time(int h,int m,int s){    hour=h;    minute=m;    sec=s;}class Date{public:    Date(int,int,int);    friend void display(const Date &,const Time &);private:    int month;    int day;    int year;};Date::Date(int m,int d,int y){    month=m;    day=d;    year=y;}void display(const Date &d,const Time &t){    cout<<d.month<<"/"<<d.day<<"/"<<d.year<<endl;    cout<<t.hour<<":"<<t.minute<<":"<<t.sec<<endl;}int main(){    Time t1(10,13,56);    Date d1(12,25,2004);    display(d1,t1);    return 0;}

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