// JavaScript source code
"use strict";

let myFunc = (input) => {
    input = input.split("\n");
    let S = input[1].split(" ");
    let N = parseInt(input[0]);
    let P, W, G, Y;
    P = W = G = Y = 0;
    for(let i = 0; i < N; i++){
        if(S[i] === 'P') P = 1;
        if(S[i] === 'W') W = 1;
        if(S[i] === 'G') G = 1;
        if(S[i] === 'Y') Y = 1;
    }
    if(P + W + G + Y === 3) console.log("Three");
    if(P + W + G + Y === 4) console.log("Four");
};

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