#include"bits/stdc++.h" using namespace std; int main() { int T; cin >> T; vector X(T+1,0); for(int i=1; i<=T; i++) cin >> X[i]; bool flag=true; for (int i = 1; i <= T; i++) { if ((X[i - 1] + 1) != X[i] && (X[i - 1] - 1) != X[i]) { flag=false; break; } } cout << (flag?"T":"F") << endl; }