#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using PII = std::pair<int, int>;
using PLL = std::pair<ll, ll>;

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rep2(i, s, n) for (int i = (s); i < (int)(n); i++)


int timetoint(int d, string t)
{
    return d * 1440 + stoi(t.substr(0, 2)) * 60 + stoi(t.substr(3, 2));
}

int main()
{

#ifdef DEBUG
    cout << "DEBUG MODE" << endl;
    ifstream in("input.txt"); //for debug
    cin.rdbuf(in.rdbuf());    //for debug
#endif
    int n, x, s;
    bool ans = true;
    cin >> n;
    s = 0;
    
    rep(i, n)
    {
        cin >> x;
        if (abs(s - x) != 1)
            ans = false;
        s = x;
    }
    
    cout << (ans ? "T" : "F" ) << endl;
    
    
    return 0;
}