#include<cstdio>
#include<iostream>
using namespace std;
bool ok;
int main()
{
	char a;
	while(cin>>a)
	{
		if(a=='C'&&ok==0)
		ok=1;
		if(a=='F'&&ok==1)
		{
			printf("Yes\n");
			return 0;
		}
	}
	printf("No\n");
	return 0;
}