#include <iostream>
#include <string>
#include <map>
#include <vector>

const std::map<char, int> letter_map{
    {'I', 1},
    {'V', 5},
    {'X', 10},
    {'L', 50},
    {'C', 100},
    {'D', 500},
    {'M', 1000}
};

int RomanToInt(const std::string & s) {
    int len = s.length();
    std::vector<int> values(len);
    for (int i = 0; i < len; ++i) {
        values[i] = letter_map.at(s[i]);
    }
    int res = values[len - 1];
    for (int i = 0; i + 1 < len; ++i) {
        if (values[i] < values[i + 1]) {
            res -= values[i];
        } else {
            res += values[i];
        }
    }
    return res;
}

int main() {
	// your code goes here
    std::string s;
    std::cin >> s;
    std::cout << RomanToInt(s) << std::endl;
	return 0;
}