//
// Program to test "next_time" function.
//

#include <iostream.h>
#include <stdlib.h>
#include <iomanip.h>		// has setw(), setfill()

// "error_exit" function.
// Post:  "Bad input" printed; program exited.
// (Yes, this is extremely crude.)
void error_exit(void)
{
  cout << "Bad input\n";
  exit(EXIT_FAILURE);
}

// "next_time" function.
// Pre:  "hours", "minutes", "seconds" represent a time in 24-hour
//         (military) format, e.g. 14:00:01.
// Post:  Prints the next time (1 second later).
void next_time(int hours, int minutes, int seconds)
{
  // check for acceptable values.
  if ((hours < 0) || (hours > 23)) error_exit();
  if ((minutes < 0) || (minutes > 59)) error_exit();
  if ((seconds < 0) || (seconds > 59)) error_exit();

  // compute next second.
  seconds = seconds + 1;

  // next minute?
  if (seconds > 59)
    {
      minutes = minutes + 1;
      seconds = 0;
    }

  // next hour?
  if (minutes > 59)
    {
      hours = hours + 1;
      minutes = 0;
    }

  // next day?
  if (hours > 23)
    {
      hours = 0;
    }

  // print result.
  cout << "next time:  "
       << setw(2) << setfill('0') << hours << ":"
       << setw(2) << setfill('0') << minutes << ":"
       << setw(2) << setfill('0') << seconds << endl;
  return;
}

int main(void)
{
  int h, m, s;
  cout << "Enter integers for hours, minutes, seconds:\n";
  cin >> h >> m >> s;
  next_time(h, m, s);
  return EXIT_SUCCESS;
}