import java.util.*

fun main(args: Array<String>) {
    val sc = Scanner(System.`in`)
    val N = sc.nextInt()

    var P = 0
    var W = 0
    var G = 0
    var Y = 0
    for (i in 0 until N) {
        val s = sc.next().toString()
        if (s == "P") P++
        if (s == "W") W++
        if (s == "G") G++
        if (s == "Y") Y++
    }
    if (P > 0 && W > 0 && G > 0 && Y > 0) {
        println("Four")
    } else {
        println("Three")
    }
}
