import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int T = scan.nextInt();
		int []X = new int[T];
		for(int i = 0; i < T; i++) {
			X[i] = scan.nextInt();
		}
		scan.close();
		if(X[0] == 0) {
			System.out.println("F");
			System.exit(0);
		}
		if(T== 1) {
			if(!(X[0] == 1 || X[0] == -1)) {
				System.out.println("F");
				System.exit(0);
			}
		}
		for(int i = 0; i < T - 1; i++) {
			int k = X[i + 1] - X[i];
			if(k * k != 1) {
				System.out.println("F");
				System.exit(0);
			}
		}
		System.out.println("T");
	}
}