import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String title = in.next().trim();
        in.close();

        // Validate: only uppercase A–Z allowed
        if (!title.matches("[A-Z]+")) {
            System.out.println("Invalid input");
            return;
        }

        int columnNumber = 0;
        for (int i = 0; i < title.length(); i++) {
            columnNumber = columnNumber * 26 + (title.charAt(i) - 'A' + 1);
        }

        System.out.println(columnNumber);
    }
}