CaesarCipher.java

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

    // Complete the caesarCipher function below.
    static String caesarCipher(String talk, int k) {
         k = k % 26 + 26;
        StringBuilder encoded = new StringBuilder();
        for (char i : talk.toCharArray()) {
            if (Character.isLetter(i)) {
                if (Character.isUpperCase(i)) {
                    encoded.append((char) ('A' + (i - 'A' + k) % 26 ));
                }
                else {
                    encoded.append((char) ('a' + (i - 'a' + k) % 26 ));
                }
            }
            else {
                encoded.append(i);
            }
        }
        return encoded.toString();

    }

    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) throws IOException {
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        int n = scanner.nextInt();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

        String s = scanner.nextLine();

        int k = scanner.nextInt();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

        String result = caesarCipher(s, k);

        bufferedWriter.write(result);
        bufferedWriter.newLine();

        bufferedWriter.close();

        scanner.close();
    }
}