#include <iostream>
using namespace std;

int main() {
    const char *rs[] = {"M", "CM", "D", "CD", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I"};
    const int rn[] = {1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1};
    int n1, n2;
    cin >> n1 >> n2;
    int n = n1-n2;
    if (n < 0)
        n = -n;
    for (int i = 0; i < 13; i++) {
        while (n >= rn[i]) {
            n -= rn[i];
            cout << rs[i];
        }
    }
}