Меняем , вводимое время, местами,
Что это тебе даст , спросишь ты?! Практика, дружок!!!. :)

//------------------------------------------------------------------------------------------------
#include <iostream>
#include <conio.h>
using namespace std;
struct Time
{
int hour;
int min;
int sec;
};
void swap(Time&, Time&);
//------------------------------------------------
int main()
{
char ch=':';
Time time1={12, 13, 15};
Time time2={13, 20, 30};
cout<<"Time 1 : "<<time1.hour<<ch<<time1.min<<ch<<time1.sec<<endl;
cout<<"Time 2 : "<<time2.hour<<ch<<time2.min<<ch<<time2.sec<<endl<<endl;
cout<<"Menyaem mestami Time! Xa!!!"<<endl<<endl;
swap(time1, time2);
cout<<"Time 1 : "<<time1.hour<<ch<<time1.min<<ch<<time1.sec<<endl;
cout<<"Time 2 : "<<time2.hour<<ch<<time2.min<<ch<<time2.sec<<endl;
getch();
return 0;
}
//------------------------------------------------------
void swap(Time& t1, Time& t2)
{
Time temp;
temp=t1;
t1=t2;
t2=temp;
}
//------------------------------------------------------------------------------------------------