function Main(input) {
	input = input.trim();
  if(input.indexOf("C") == -1 || input.indexOf("F") == -1){
     console.log("No");
    return;
  }
  var list = [];
  for(var i = 0; i < input.length; i++){
    var tmp = input.slice(i,i+1);
    if(tmp == "C" || tmp == "F"){
       list.push(tmp);
       }
  }
  list = list.join("");
  console.log((list.indexOf("CF") != -1) ? "Yes" : "No");
}

Main(require("fs").readFileSync("/dev/stdin", "utf8"));
