import std.stdio;
import std.conv, std.array, std.algorithm, std.string;
import std.math, std.random, std.range, std.datetime;
import std.bigint;

void main(){
	string s = readln.chomp;
	
	int f = 0;
	foreach(c; s){
		if(f == 0 && c == 'C') f = 1;
		if(f == 1 && c == 'F') f = 2;
		}
	
	string ans;
	if(f == 2) ans = "Yes";
	else ans = "No";
	
	ans.writeln;
	
	}