#include<bits/stdc++.h>
using namespace std;int main(){char s[10000];int len;scanf("%s",s+1);int flag=0;for(int i=1;i<=strlen(s+1);++i){if(flag==0&&s[i]=='C')flag=1;if(flag==1&&s[i]=='F')flag=2;}if(flag==2)puts("Yes");else puts("No");}