Download All Files (as .zip)

A day on Mars is just a little bit longer than a day on Earth. One day on Mars lasts 24 hours 37 minutes and 22.663 seconds in Earth time. To make sure they can get the most out of the daylight hours on Mars, when NASA plans a Mars Rover mission, they put all of their employees on "Martian Time".

Martian time uses a 24-hour clock divided into minutes and seconds just like Earth time. But every Martian hour, minute and second has to be just a little bit longer than its Earth counterpart.

It just so happens that at 12:00 AM on January 1^{st}, 2015 (aka Day 1) on Earth it will also be exactly
12:00 AM of Day 1 in Martian time at the place where the next Mars rover will touch down. So NASA has issued its employees Martian
digital watches, synchronized so that Day 1 at midnight matches Day 1 at midnight on Earth. These watches report the day, hour and
minute of the current time (they keep track of seconds as well, but don't report that number on the face of the watch).

DATA11.txt (DATA12.txt for the second try) will contain 10 test cases. Each test case will consist of three integers D, H, and M
representing the Day, Hour and Minute of an exact time on Earth, where Day 1 is January 1^{st}, 2015
(1 ≤ D ≤ 1000, 0 ≤ H ≤ 23 and 0 ≤ M ≤ 59). Your job is to output the current time on Mars as it would be shown
on the Martian digital watch described above. Each time should be on a single line and formatted exactly as shown in the sample output below.

346 12 28 393 06 40 390 19 50 984 02 25 674 21 29 435 13 07 15 04 12 539 00 50 40 01 20 69 03 11Sample Input

Day 337, 18:40 Day 383, 08:28 Day 380, 23:07 Day 959, 05:28 Day 657, 20:17 Day 424, 13:15 Day 14, 19:35 Day 525, 10:08 Day 39, 01:37 Day 67, 09:48Sample Output

Note: in my current solution, I only get the correct output when I add 36 minutes to whatever I calculated.
I'm not sure why it works yet and what the problem is with the other part of my code, but I'm working on it.
In both algorithm methods, I have`mins += 36;`

and `marsSeconds += 2160;`

.
One of them is commented out in each (alternating ones) so that it doesn't add 72 minutes in total, but I show boths
ways of doing it just for different ways of thinking. One way is adding 36 minutes in seconds at the beginning,
the other is adding 36 minutes in minutes after the minutes are already calculated.

import java.text.DecimalFormat; import java.util.ArrayList; import java.util.Scanner; import java.io.File; public class Problem_1_Martian_Time { public static final double RATIO = 86400 / 88642.663; // earth day : mars day (in seconds) public static final DecimalFormat DF = new DecimalFormat("00"); // just to format the output public static void main(String[] args) { try { Scanner scanner = new Scanner(new File("F:\\data\\DATA11.txt")); ArrayList<String> list = new ArrayList<String>(); // read in the file to the ArrayList while (scanner.hasNextLine()) { list.add(scanner.nextLine()); } for (String line : list) { String[] s = line.split("\\s+"); // split line by white space int day = Integer.parseInt(s[0]); int hour = Integer.parseInt(s[1]); int minute = Integer.parseInt(s[2]); /* Convert Earth time from days, hours and minutes into seconds then figure out that Mars time in seconds then convert the Mars time from seconds to days, hours and minutes. */ // choose one or the other (both algorithms give the same output) differenceAlgorithm(day, hour, minute); moduloAlgorithm(day, hour, minute); } } catch (Exception e) { e.printStackTrace(); } } /* Independent of moduloAlgorithm, this method is one solution */ public static void differenceAlgorithm(int d, int h, int m) { // 60 seconds in a minute, 60 minutes in an hour, 24 hours in a day double earthSeconds = d * 60 * 60 * 24 + h * 60 * 60 + m * 60; double marsSeconds = earthSeconds * RATIO; marsSeconds += 2160; // add 36 minutes (it works for some reason) int days = (int)marsSeconds / 86400; // whole number of days int daysInSeconds = days * 86400; // whole days represented in seconds // seconds left to be distributed to the hours and minutes (days are done) double secondsLeft = marsSeconds - daysInSeconds; int hours = (int)(secondsLeft / 3600); // whole number of hours int hoursInSeconds = hours * 3600; // whole hours represented in seconds // seconds left to be distributed to the minutes (days and hours are done) secondsLeft = marsSeconds - daysInSeconds - hoursInSeconds; double minutes = secondsLeft / 60; // minutes += 36; // add 36 minutes (it works for some reason) // needs to be here in case the minutes get rounded up to an hour if (minutes >= 59.5) { hours += 1; minutes -= 60; if (hours >= 24) { days += 1; hours -= 24; } } System.out.print("Day " + days + ", "); System.out.print(DF.format(hours) + ":"); System.out.println(DF.format(Math.abs(minutes))); // absolute value so negative number rounded doesn't show negative sign } /* Independent of differenceAlgorithm, this method is one solution */ public static void moduloAlgorithm(int d, int h, int m) { // 60 seconds in a minute, 60 minutes in an hour, 24 hours in a day double earthSeconds = d * 60 * 60 * 24 + h * 60 * 60 + m * 60; double marsSeconds = earthSeconds * RATIO; // marsSeconds += 2160; // add 36 minutes (it works for some reason) int days = (int)marsSeconds / 86400; // whole number of days // remainder from factoring out the days double secondsLeft = marsSeconds % 86400; // whole number of hours int hours = (int)(secondsLeft / 3600); // remainder from factoring out the hours secondsLeft %= 3600; double minutes = secondsLeft / 60; minutes += 36; // add 36 minutes (it works for some reason) // needs to be here in case the minutes get rounded up to an hour if (minutes >= 59.5) { hours += 1; minutes -= 60; if (hours >= 24) { days += 1; hours -= 24; } } System.out.print("Day " + days + ", "); System.out.print(DF.format(hours) + ":"); System.out.println(DF.format(Math.abs(minutes))); // absolute value so negative number rounded doesn't show negative sign } }

DOWNLOAD as .java
## My test cases (as .txt files):

Using their sample input:

346 12 28 393 06 40 390 19 50 984 02 25 674 21 29 435 13 07 15 04 12 539 00 50 40 01 20 69 03 11

And the output to that is:

Day 337, 18:40 Day 383, 08:28 Day 380, 23:07 Day 959, 05:28 Day 657, 20:17 Day 424, 13:15 Day 14, 19:35 Day 525, 09:32 Day 39, 01:37 Day 67, 09:48DOWNLOAD as .txt

Using their first judging test input:

477 09 44 19 22 59 120 02 48 390 09 45 880 23 24 797 15 27 809 14 34 242 19 49 313 05 46 168 00 59

And the output to that is:

Day 465, 08:27 Day 19, 11:28 Day 117, 02:28 Day 380, 13:18 Day 858, 17:04 Day 777, 11:43 Day 789, 03:34 Day 236, 16:58 Day 305, 08:10 Day 163, 19:33DOWNLOAD as .txt

And that is exactly the expected output.

Using their second judging test input:

225 11 38 917 10 12 57 01 49 70 19 19 31 05 57 463 10 43 63 11 07 205 07 08 119 10 26 703 14 12

And the output to that is:

Day 219, 19:19 Day 894, 05:44 Day 55, 15:46 Day 69, 00:55 Day 30, 11:35 Day 451, 17:55 Day 61, 21:11 Day 200, 03:05 Day 116, 10:31 Day 685, 19:35DOWNLOAD as .txt

And that is exactly the expected output.

Created: April 2, 2014

Completed in full by: Michael Yaworski