// Class Clock is used to store a time

// Comparable<E>

public class Clock implements Comparable<E> {
  private int hours;
  private int minutes;

  // pre: minutes >= 0 and minutes < 60
  // pre: hours >= 0
  public Clock(int hours, int minutes) {
    if (minutes < 0 || minutes >= 60 || hours < 0) {
      throw new IllegalArgumentException();
    }
    this.hours = hours;
    this.minutes = minutes;
  }

  // post: returns the integer hours for this clock
  public int getHours() {
    return hours;
  }

  // post: returns the minutes portion of this clock (not counting hours)
  public int getMinutes() {
    return minutes;
  }

  public String toString() {
    return hours + "h " + minutes + "m";
  }

  public Clock add(Clock other) {
    int newHours = hours + other.hours;
    int newMinutes = minutes + other.minutes;
    if (newMinutes > 59) {
      newHours++;
      newMinutes -= 60;
    }
    Clock newClock = new Clock(newHours, newMinutes);
    return newClock;
  }  
  
  // this < other: return number < 0
  // this > other: return number > 0
  // this == other: return 0
  public int compareTo(Clock other) {
    if (hours > other.hours) {
      return 1;
    } else if (hours < other.hours) {
      return -1;
    } else {
      // compare minutes
      return minutes - other.minutes;
    }
  }       
}