#include<bits/stdc++.h>
using namespace std;
const int N=1010;
int bj=0;
char s;
int main(){
	while(cin>>s){
		if(s=='C') bj=1;
		if(bj==1 && s=='F') {
			cout<<"Yes"<<endl;
			return 0;
		}
	}
	cout<<"No"<<endl;
	return 0;
}