#include <cstdio>
using namespace std;

char c;
int a, b;

int main () {
	while (~(c = getchar ())) {
		if (c == 'C') a = 1;
		else if (c == 'F' && a) b = 1;
	}
	puts (a && b ? "Yes" : "No");
	return 0;
}