import java.util.*

fun main(args: Array<String>) {
    val sc = Scanner(System.`in`)
    val s = sc.next()
    val left = s.indexOf("C")
    val right = s.lastIndexOf("F")
    if (left != -1 && right != -1 && left < right) {
        println("Yes")
    } else {
        println("No")
    }
}