#define _USE_MATH_DEFINES #include //cin, cout #include //vector #include //sort,min,max,count #include //string,getline, to_string #include //abs(int) #include //swap, pair #include //tuple #include //deque #include //INT_MAX #include //bitset #include //sqrt, ceil. M_PI, pow, sin #include //fixed #include //setprecision #include //stringstream #include //gcd, assumlate #include //randam_device #include //numeric_limits using namespace std; constexpr long long int D_MOD = 1000000007; int main() { int T; cin >> T; int a, b; cin >> a; if (a == 0) { cout << "F" << endl; return 0; } for (int i = 1; i < T; i++) { cin >> b; if (abs(b - a) == 1) { a = b; } else { cout << "F" << endl; return 0; } } cout << "T" << endl; return 0; }