import std.algorithm;
import std.array;
import std.ascii;
import std.container;
import std.conv;
import std.math;
import std.numeric;
import std.range;
import std.stdio;
import std.string;
import std.typecons;

void log(A...)(A arg) {
    stderr.writeln(arg);
}
int size(T)(in T s) {
    return cast(int)s.length;
}

void main() {
    auto s = readln.chomp;
    int x = 0;
    foreach (c; s) {
        if (c == 'C') {
            if (x == 0) x++;
        } else if (c == 'F') {
            if (x == 1) x++;
        }
    }
    writeln(x == 2 ? "Yes" : "No");
}
