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

int main()
{
	string s;
	cin>>s;
	for(int i=0;i<s.length();i++)
		for(int j=i+1;j<s.length();j++)
		if(s[i]=='C'&&s[j]=='F')
		{
			cout<<"Yes";
			return 0;
		}
		cout<<"No";
	return 0;
}