#include <iostream>
#include <vector>
#include <map>
#include <set>
#include <string>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <stdio.h>
using namespace std;
#define int long long
signed main() {
	int T;
	cin >> T;
	vector<int> x(T);
	for (int i = 0; i < T; i++) {
		cin >> x[i];
	}
	int pos = 0;
	for (int i = 0; i < T; i++) {
		if (abs(pos - x[i]) != 1) {
			cout << "F" << endl;
			return 0;
		}
		pos = x[i];
	}
	cout << "T" << endl;
	return 0;
}