#include using namespace std; typedef long long ll; #define rep(i, n) for(ll i = 0, i##_len = (n); i < i##_len; i++) #define reps(i, s, n) for(ll i = (s), i##_len = (n); i < i##_len; i++) #define rrep(i, n) for(ll i = (n) - 1; i >= 0; i--) #define rreps(i, e, n) for(ll i = (n) - 1; i >= (e); i--) #define all(x) (x).begin(), (x).end() #define sz(x) ((ll)(x).size()) #define len(x) ((ll)(x).length()) int main() { cin.tie(0); ios::sync_with_stdio(false); // ifstream in("input.txt"); // cin.rdbuf(in.rdbuf()); ll n; cin >> n; ll before = 0; rep(i, n) { ll a; cin >> a; if (abs(before - a) != 1) { cout << "F" << endl; return 0; } before = a; } cout << "T" << endl; return 0; }