import java.util.Scanner;

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

		String s = sc.next();
		System.out.println(decrypt(s));

		sc.close();
	}

	static char cDecrypt(char c, int i) {
		return (char)('A' + ((c - i % 26) - 'A' + 26) % 26);
	}

	static String decrypt(String s) {
		String re = "";
		for (int i = 0; i < s.length(); i++)
			re += cDecrypt(s.charAt(i), i + 1);
		return re;
	}
}