类练习

#include<iostream>
using namespace std;
class date;
class time
{
public:
time(int,int,int);
void display(date &);
private:
int hour,minu,sec;
};
class date
{
public:
date(int,int,int);
friend void time::display(date &);
private:
int year,month,day;
};
time::time(int h,int m,int s)
{
hour=h;
minu=m;
sec=s;
}
date::date(int y,int m,int d)
{
year=y;
month=m;
day=d;
}
void time::display(date &d1)
{
cout<<d1.year<<":"<<d1.month<<":"<<d1.day<<endl;
cout<<hour<<":"<<minu<<":"<<sec<<endl;
}
void main()
{
time t1(23,31,24);
date d1(2014,2,3);
t1.display(d1);
}

 

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

time::time(int h,int m,int s)
{
hour=h;
minu=m;
sec=s;
}
date::date(int y,int m,int d)
{
year=y;
month=m;
day=d;
}
void date::display(time &t)
{
cout<<year<<"/"<<month<<"/"<<day<<endl;
cout<<t.hour<<":"<<t.minu<<":"<<t.sec;
}
void main()
{
date d1(2014,2,5);
time t1(11,1,1);
d1.display(t1);
}