package TextAndRegexExercise;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class LettersChangeNumbers_14 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String[] input = scanner.nextLine().split("\\s+");
        double finalNumber = 0.0;
        double currentNumber = 0.0;

        List<Character> lowercase = new ArrayList<>();
        List<Character> uppercase = new ArrayList<>();

        lowercase.add('@');
        uppercase.add('@');

        for (int i = 'A'; i <= 'Z'; i++) {
            uppercase.add((char) i);
        }
        for (int i = 'a'; i <= 'z'; i++) {
            lowercase.add((char) i);
        }
        for (int i = 0; i < input.length; i++) {
            currentNumber = 0.0;
            String currentWord = input[i];
            char before = currentWord.charAt(0);
            char after = currentWord.charAt(currentWord.length() - 1);
            int number = Integer.parseInt(currentWord.substring(1, currentWord.length() - 1));
            if (uppercase.contains(before)) {
                int beforeIndex = uppercase.indexOf(before);
                currentNumber = (double) number / beforeIndex;
            }
            if (lowercase.contains(before)) {
                int beforeIndex = lowercase.indexOf(before);
                currentNumber = number * beforeIndex;
            }
            if (uppercase.contains(after)) {
                int afterIndex = uppercase.indexOf(after);
                currentNumber -= afterIndex;
            }
            if (lowercase.contains(after)) {
                int afterIndex = lowercase.indexOf(after);
                currentNumber += afterIndex;
            }

            finalNumber += currentNumber;
        }
        System.out.printf("%.2f",finalNumber);
    }
}