object Main{
  def main(args: Array[String]){
    val input=io.Source.stdin.getLines().mkString("\n");
    println(solve(input).trim());
  }

  def solve(input:String):String={
    if(input.split("\n")(1).split(" ").contains("Y")){
      "Four"
    }else{
      "Three"
    }
  }
}
