# -*- coding:utf-8 -*-
T = int(input())
input_list = [int(input()) for _ in range(T)]
input_list.insert(0, 0)

flag = True
for i in range(len(input_list) - 1):
    diff = input_list[i+1] - input_list[i]
    if diff != 1 and diff != -1:
        flag = False

ans = 'T' if flag else 'F'
print(ans)