#include<iostream>
using namespace std;
class date;
class time
{
public:
time(int ,int,int);
void display(date&);
private:
int hour;
int minute;
int sec;
};

class date
{
public:
date(int,int,int);
friend void time::display(date&);
private:
int month;
int day;
int year;
};

time::time(int h,int m,int s)
{
hour=h;
minute=m;
sec=s;
}

void time::display(date&d)
{
    cout<<d.month<<"/"<<d.day<<"/"<<d.year<<endl;//注意d.day必须要指定对象访问
    cout<<hour<<":"<<minute<<":"<<sec<<endl;//这里hour等本来就是display成员函数的私有数据可以直接访问
}

date::date(int m,int d,int y)
{
month=m;
day=d;
year=y;
}

int main()
{
time t1(10,13,56);
date d1(12,23,2004);
t1.display(d1);
return 0;
}