Java Date and Time Hackerrank Challenge

Java/JavaDateAndTime/Solution.java

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+import java.io.*;
+import java.math.*;
+import java.security.*;
+import java.text.*;
+import java.util.*;
+import java.util.concurrent.*;
+import java.util.regex.*;
+
+class Result {
+
+    /*
+     * Complete the 'findDay' function below.
+     *
+     * The function is expected to return a STRING.
+     * The function accepts following parameters:
+     *  1. INTEGER month
+     *  2. INTEGER day
+     *  3. INTEGER year
+     */
+
+    public static String findDay(int month, int day, int year) {
+                int yearDividedBy4 = (year % 100)/4;
+        int YY = year % 100;
+
+        int yearSum = yearDividedBy4 + YY;
+
+        int yearCode = yearSum % 7;
+
+        int monthCode = 0;
+
+        switch(month){
+            case 1:
+                monthCode = 0;
+                break;
+            case 2:
+                monthCode = 3;
+                break;
+            case 3:
+                monthCode = 3;
+                break;
+            case 4:
+                monthCode = 6;
+                break;
+            case 5:
+                monthCode = 1;
+                break;
+            case 6:
+                monthCode = 4;
+                break;
+            case 7:
+                monthCode = 6;
+                break;
+            case 8:
+                monthCode = 2;
+                break;
+            case 9:
+                monthCode = 5;
+                break;
+            case 10:
+                monthCode = 0;
+                break;
+            case 11:
+                monthCode = 3;
+                break;
+            case 12:
+                monthCode = 5;
+                break;
+            default:
+                monthCode = 0;
+        }
+
+        int leapYearCode = (year % 4 == 0 && (month == 1 || month == 2)) ? 1 : 0;
+
+        int centuryCode = 0;
+
+        // If the year is greater than 2200, then "standardize" the year by subtracting 400 until you get a year that is within 1752 and 2200 in order to determine the century code below 
+        if (year > 2200){
+            while (year > 2200){
+                year -= 400;
+            }
+        }
+
+        if (year > 2200 && year < 2300){
+            centuryCode = 2;
+        } else if (year > 2100){
+            centuryCode = 4;
+        } else if (year > 2000) {
+            centuryCode = 6;
+        } else if (year > 1900) {
+            centuryCode = 0;
+        } else if (year > 1800) {
+            centuryCode = 2;
+        // 1752 was the year that calendar transitioned from Julian Calendar to Gregorian Calendar
+        } else if (year > 1752) {
+            centuryCode = 4;
+        // September 1752 was the month that calendar transitioned from Julian Calendar to Gregorian Calendar
+        } else if (year == 1752 && month >= 9){
+            centuryCode = 4;
+        // September 14th, 1752 was the date that calendar transitioned from Julian Calendar to Gregorian Calendar
+        } else if (year == 1752 && month == 9 && day >= 14){
+            centuryCode = 4;
+        } else if (year >= 0){
+            centuryCode = (18 - (year / 100)) % 7;
+        }
+
+        int result = yearCode + monthCode + centuryCode + day - leapYearCode;
+
+        switch (result % 7){
+            case 0:
+                return "SUNDAY";
+            case 1:
+                return "MONDAY";
+            case 2:
+                return "TUESDAY";
+            case 3:
+                return "WEDNESDAY";
+            case 4:
+                return "THURSDAY";
+            case 5:
+                return "FRIDAY";
+            default:
+                return "SATURDAY";
+        }
+    }
+}
+
+public class Solution {
+    public static void main(String[] args) throws IOException {
+        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
+        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));
+
+        String[] firstMultipleInput = bufferedReader.readLine().replaceAll("\\s+$", "").split(" ");
+
+        int month = Integer.parseInt(firstMultipleInput[0]);
+
+        int day = Integer.parseInt(firstMultipleInput[1]);
+
+        int year = Integer.parseInt(firstMultipleInput[2]);
+
+        String res = Result.findDay(month, day, year);
+
+        bufferedWriter.write(res);
+        bufferedWriter.newLine();
+
+        bufferedReader.close();
+        bufferedWriter.close();
+    }
+}