#include<bits/stdc++.h>
using namespace std;
char a[101];int j;
int main(){
	cin>>a;
	int l=strlen(a);
	for (int i=0;i<=l;i++){if (j==1&&a[i]=='F'){printf("Yes");return 0;}if (j==0&&a[i]=='C') j=1;}
	printf("No");
	return 0;
}