import java.util.*;

public class Main {
    // Map for Roman numeral values
    private static final Map<Character, Integer> romanMap = new HashMap<>();
    static {
        romanMap.put('I', 1);
        romanMap.put('V', 5);
        romanMap.put('X', 10);
        romanMap.put('L', 50);
        romanMap.put('C', 100);
        romanMap.put('D', 500);
        romanMap.put('M', 1000);
    }

    // Convert Roman to Integer
    public static int romanToInt(String s) {
        int total = 0;
        int prev = 0;

        for (int i = s.length() - 1; i >= 0; i--) {
            int value = romanMap.get(s.charAt(i));
            if (value < prev) {
                total -= value;  // subtraction rule
            } else {
                total += value;
            }
            prev = value;
        }
        return total;
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String input = sc.nextLine().trim();

        // Case 1: Negative roman (starts with '-')
        if (input.startsWith("-")) {
            System.out.println(-1);
            return;
        }

        // Case 2: Check for invalid characters or lowercase
        for (char c : input.toCharArray()) {
            if (!romanMap.containsKey(c)) {
                System.out.println("Invalid input");
                return;
            }
        }

        // Case 3: Valid Roman → Convert
        int result = romanToInt(input);
        System.out.println(result);
    }
}