6.10: time3.h
// Declaration of the Time class.
// Member functions defined in time3.cpp

// preprocessor directives that
// prevent multiple inclusions of header file
#ifndef TIME3_H  
#define TIME3_H 

class Time {
public:
   Time( int = 0, int = 0, int = 0 );  // constructor

   // set functions
   void setTime( int, int, int );  // set hour, minute, second
   void setHour( int );   // set hour
   void setMinute( int ); // set minute
   void setSecond( int ); // set second

   // get functions
   int getHour();         // return hour
   int getMinute();       // return minute
   int getSecond();       // return second

   void printMilitary();  // output military time
   void printStandard();  // output standard time

private:
   int hour;              // 0 - 23
   int minute;            // 0 - 59
   int second;            // 0 - 59
};

#endif
ig. 6.10: time3.cpp
// Member function definitions for Time class.
#include "time3.h"
#include <iostream.h>

// Constructor function to initialize private data.
// Calls member function setTime to set variables.
// Default values are 0 (see class definition).
Time::Time( int hr, int min, int sec ) 
   { setTime( hr, min, sec ); }

// Set the values of hour, minute, and second.
void Time::setTime( int h, int m, int s )
{
   setHour( h );
   setMinute( m );
   setSecond( s );
}

// Set the hour value
void Time::setHour( int h ) 
   { hour = ( h >= 0 && h < 24 ) ? h : 0; }

// Set the minute value
void Time::setMinute( int m )
   { minute = ( m >= 0 && m < 60 ) ? m : 0; }

// Set the second value
void Time::setSecond( int s )
   { second = ( s >= 0 && s < 60 ) ? s : 0; }

// Get the hour value
int Time::getHour() { return hour; }

// Get the minute value
int Time::getMinute() { return minute; }

// Get the second value
int Time::getSecond() { return second; }

// Print time is military format
void Time::printMilitary()
{
   cout << ( hour < 10 ? "0" : "" ) << hour << ":"
        << ( minute < 10 ? "0" : "" ) << minute;
}

// Print time in standard format
void Time::printStandard()
{
   cout << ( ( hour == 0 || hour == 12 ) ? 12 : hour % 12 ) 
        << ":" << ( minute < 10 ? "0" : "" ) << minute 
        << ":" << ( second < 10 ? "0" : "" ) << second
        << ( hour < 12 ? " AM" : " PM" );
}
// Demonstrating the Time class set and get functions
#include <iostream.h>
#include "time3.h"

void incrementMinutes( Time &, const int );

int main()
{
   Time t;

   t.setHour( 17 );
   t.setMinute( 34 );
   t.setSecond( 25 );

   cout << "Result of setting all valid values:\n" 
        << "  Hour: " << t.getHour()
        << "  Minute: " << t.getMinute()
        << "  Second: " << t.getSecond();

   t.setHour( 234 );    // invalid hour set to 0
   t.setMinute( 43 );
   t.setSecond( 6373 ); // invalid second set to 0

   cout << "\n\nResult of attempting to set invalid hour and"
        << " second:\n  Hour: " << t.getHour()
        << "  Minute: " << t.getMinute()
        << "  Second: " << t.getSecond() << "\n\n";
   t.setTime( 11, 58, 0 );
   incrementMinutes( t, 3 );

   return 0;
}

void incrementMinutes(Time &tt, const int count)
{
   cout << "Incrementing minute " << count
        << " times:\nStart time: ";
   tt.printStandard();

   for ( int i = 0; i < count; i++ ) {
      tt.setMinute( ( tt.getMinute() + 1 ) % 60);

      if ( tt.getMinute() == 0 )
         tt.setHour( ( tt.getHour() + 1 ) % 24);

      cout << "\nminute + 1: ";
      tt.printStandard();
   }

   cout << endl;
}