import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter message: ");
        String message = scanner.nextLine();

        System.out.print("Enter shift value (N): ");
        int shift = scanner.nextInt();

        String encrypted = encrypt(message, shift);
        System.out.println("Encrypted Message: " + encrypted);
        
        String decrypted = encrypt(encrypted, 26 - (shift % 26));
        System.out.println("Decrypted Message: " + decrypted);

        scanner.close();
    }

    public static String encrypt(String text, int shift) {
        StringBuilder result = new StringBuilder();

        for (char character : text.toCharArray()) {
            if (Character.isLetter(character)) {
                char base = Character.isUpperCase(character) ? 'A' : 'a';
                // Calculate new position: (current - base + shift) % 26 + base
                char shifted = (char) ((character - base + shift) % 26 + base);
                result.append(shifted);
            } else {
                result.append(character);
            }
        }
        return result.toString();
    }
}