#include <iostream>
#include <algorithm>
#include <climits>

using namespace std;

int main(int argc, const char *argv[]) {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    int n, k;
    double MIN = INT_MAX, MAX = 0;

    cin >> n;

    for (int i = 1; i <= n; i++) {
        double tmp;
        cin >> tmp;
        MIN = min(MIN, tmp / i);
        MAX = max(MAX, tmp / i);
    }

    cin >> k;

    if (k >= MIN && k <= MAX) {
        cout << 'T' << endl;
    } else {
        cout << 'F' << endl;
    }

    return 0;
}