#include <bits/stdc++.h>

using namespace std;

int main() {
	int n;
	cin >> n;
	for (int i=0;i < n;i++) {
		string s;
		cin >> s;
		if (s == "Y") {
			cout << "Four";
			return 0;
		}
	}
	cout << "Three";
	return 0;
}
