#include <bits/stdc++.h>
using namespace std;
int main() {
	string s;
	cin >> s;
	int x = 0;
	for (char c : s) {
		if (x == 0 && c == 'C') x = 1;
		else if (x == 1 && c == 'F') x = 2;
	}
	cout << (x == 2 ? "Yes" : "No") << endl;
}
