class Program
{
    static void Main(string[] args)
    {
        int count = int.Parse(Console.ReadLine()!);
        bool judgment = true;
        int criteria = 0;

        for (int i = 0; i < count; i++)
        {
            int num = int.Parse(Console.ReadLine()!);
            if (num == criteria + 1 ||  num == criteria - 1)
            {
                criteria = num;
            }
            else
            {
                judgment = false;
            }
        }

        if (judgment)
        {
            Console.WriteLine("T");
        }
        else
        {
            Console.WriteLine("F");
        }
    }
}