#include<bits/stdc++.h>
using namespace std;
string a;
bool cf[2]={0}; 
int main() 
{
	cin>>a;
	for(int i=0;i<a.length();i++) 
	{ 
		if(a[i]=='C') cf[0]=1;
		if(a[i]=='F'&&cf[0]) cf[1]=1;
	}
	if(cf[1]) cout<<"Yes";
	else cout<<"No";
}