#include<bits/stdc++.h>
using namespace std;

int main(){
	string S;
	cin>>S;
	int f=1;
	for(int i=0;i<S.size();i++){
		if(f==1&&S[i]=='C')f++;
		if(f==2&&S[i]=='F')f++;
	}
	if(f==3)cout<<"Yes"<<endl;
	else cout<<"No"<<endl;
	
	return 0;
} 