# coding: utf-8
n = int(input())
data = []
for i in range(n):
    data.append(int(input()))

checker = 0

if data[0] != 1 and data[0] != -1:
    checker += 1

for j in range(n - 1):
    if abs(data[j + 1] - data[j]) != 1:
        checker += 1

if checker == 0:
    print('T')
else:
    print('F')