Java: Converting an input of seconds into hours/minutes/seconds

Question

This is an exercise question taken from Java Software Solutions: foundations of program design by Lewis & Loftus, 4th edition ; Question PP2.6 (here is a link)

Answer 1

Here is a much simpler way of doing it:

public static void main (String[] args) throws Exception {
    SimpleDateFormat sf = new SimpleDateFormat("HH:mm:ss");
    TimeZone.setDefault(TimeZone.getTimeZone("GMT"));
    System.out.println(sf.format(new Date(9999000)));
}

Note: Please note that this will only show the output in 24-hour format and if number of hours is greater than 24 then it'll increment a day and will start over. For example, 30 hours will be displayed as 06:xx:xx. Also, you'll have to pass the input in milliseconds instead of seconds.

If you want to do it your way then you should probably do something like this:

public static void main (String[] args) throws Exception {
    long input = 9999;
    long hours = (input - input%3600)/3600;
    long minutes = (input%3600 - input%3600%60)/60;
    long seconds = input%3600%60;
    System.out.println("Hours: " + hours + " Minutes: " + minutes + " Seconds: " + seconds);
}

Output:

Hours: 2 Minutes: 46 Seconds: 39

Answer 2

As an alternative of user2004685's answer;

int seconds = 9999; 
int hour = 9999 / (60 * 60); //int variables holds only integer so hour will be 2
seconds = 9999 % (60 * 60); // use modulo to take seconds without hours so it will be 2799
int minute = seconds / 60; //same as int variable so minute will be 49
seconds = seconds % 60; // modulo again to take only seconds
System.out.println(hour + ":" + minute + ":" + seconds);