# include <stdio.h>

//
//  Program 9.6, Stephen Kochan, Programming in C.
//
struct time
{
  int hour;
  int minutes;
  int seconds;
};

int main ( void );
struct time timeUpdate ( struct time now );

int main ( void )
{
  struct time testTimes[5] = {
    { 11, 59, 59 },
    { 12,  0,  0 },
    {  1, 29, 59 },
    { 23, 59, 59 },
    { 19, 12, 27 } };
  int i;

  for ( i = 0; i < 5; i++ )
  {
    printf ( "Time is %.2i:%.2i.%.2i\n", testTimes[i].hour,
      testTimes[i].minutes, testTimes[i].seconds );

    testTimes[i] = timeUpdate ( testTimes[i] );

    printf ( "One second later is %.2i:%.2i.%.2i\n", testTimes[i].hour,
      testTimes[i].minutes, testTimes[i].seconds );
  }
  return 0;
}

struct time timeUpdate ( struct time now )
{
  now.seconds = now.seconds + 1;

  if ( now.seconds == 60 )
  {
    now.seconds = 0;
    now.minutes = now.minutes + 1;
    if ( now.minutes == 60 )
    {
      now.minutes = 0;
      now.hour = now.hour + 1;
      if ( now.hour == 24 )
      {
        now.hour = 0;
      }
    }
  }
  return now;
}