#include <bits/stdc++.h>
using namespace std;

int main() {
  int T;
  cin >> T;
  vector<int> xs(T);
  for (int i = 0; i < T; i++) cin >> xs[i];
  int pos = 0;
  for (int i = 0; i < T; i++) {
    if (abs(pos - xs[i]) != 1) {
      cout << "F" << endl;
      return 0;
    }
    pos = xs[i];
  }
  cout << "T" << endl;
  return 0;
}