#include<cstdio>
#include<iostream>
using namespace std;
int main (){
    string b;
    cin>>b;
    if(b[1]=='X'){
        printf("X");
        }
        else if(b[1]=='I'){
            printf("I");
            }
            else if(b[1]=='I' && b[2]=='I'){
                printf("II");
                }

    return 0;
    }