#include <iostream>

using namespace std;

int main() {
    int theNumbers[]{1, 5, 10, 50, 100, 500, 1000};
    string theChar = "IVXLCDM";

    string s = "LIX";
    int sum = 0;
    for (int i = 0, previousСhar = 0, nextCrar = 0; i < s.length(); ++i) {
        for (int j = 0; j < theChar.length(); ++j) {
            if (s[i] == theChar[j]) {
                nextCrar = j;
                j = theChar.length() + 2;
            }
            if (j + 1 == theChar.length()) {
                cout << "ERROR";
                return 0;
            }
        }
        if (i == 0) {
            previousСhar = nextCrar;
            sum += theNumbers[nextCrar];
        } else {
            if (theNumbers[nextCrar] > theNumbers[previousСhar]) {
                sum = sum + theNumbers[nextCrar] - theNumbers[previousСhar];
                sum = sum - theNumbers[previousСhar];
                previousСhar = nextCrar;
            } else {
                previousСhar = nextCrar;
                sum += theNumbers[nextCrar];
            }
        }
        sum = abs(sum);
    }
    cout << endl << "Sum: " << sum;

}