An algorithm for calculating the day of the week given a Date

Given a date and calculate day of the week:

import java.util.*;

public class Datetoday {

   

   final static String[] WEEK_DAYS = {

           "Saturday", "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday",

           "Friday"

       };

   public static void main(String[] args) {

       Scanner input = new Scanner(System.in);

       System.out.print("Enter the date in dd/mm/yyyy form: ");

       String[] partofdate = input.nextLine().split("/");

       int d = Integer.parseInt(partofdate[0]);

       int m = Integer.parseInt(partofdate[1]);

       int y = Integer.parseInt(partofdate[2]);

       if (m < 3) {

           m += 12;

           y -= 1;

       }

       int k = y % 100;

       int j = y / 100;

       int day = ((d + (((m + 1) * 26) / 10) + k + (k / 4) + (j / 4)) +

           (5 * j)) % 7;

       System.out.println("That date was " + WEEK_DAYS[day] + ".");

   }

}