import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Scanner;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        Task solver = new Task();
        solver.solve(1, in, out);
        out.close();
    }

    static class Task {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            int n = in.nextInt();
            int pos = 0;
            String ans = "T";
            for (int i = 0; i < n; i++) {
                int next = in.nextInt();
                if (Math.abs(pos - next) != 1) ans = "F";
                pos = next;
            }
            out.println(ans);
        }

    }
}