mian.cpp

#include"iostream.h"
#include"myTime.h"

void main()
{
 CmyTime time;
 int hour,minute,second;
 cin>>hour>>minute>>second;
 time.setTime(hour,minute,second);
 cout<<"this time is ";
 time.showTime();
}

mytime.cpp

#include"iostream.h"
#include"myTime.h"

void CmyTime::setTime(int nHour,int nMinute,int nSecond)
{
 hour=(nHour>=0&&nHour<24)?nHour:0;
 minute=(nMinute>=0&&nMinute<60)?nMinute:0;
 second=(nSecond>=0&&nSecond<60)?nSecond:0;
}
void CmyTime::showTime()
{
 cout<<hour<<":"<<minute<<":"<<second<<endl;
}

mytime.h

class CmyTime
{
private:
 int hour;
 int minute;
 int second;
public:
 void setTime(int nHour,int nMinute,int nSecond);
 void showTime();
};