#include<iostream>
#include<cstring>
using namespace std;

int main()
{
    char s[101];
    cin>>s;
    char *p=strchr(s,'C');
    if(!p){
        cout<<"No";
        return 0;
    }
    p=strchr(p,'F');
    if(p){
        cout<<"Yes";
    }
    else
        cout<<"No";
    return 0;
}
