T = int(input().strip())
X = [int(input()) for _ in range(T)]

if T == 1:
  print('T')
  exit(0)
elif abs(X[0]) != 1:
  print('F')
  exit(0)

lst = list(set([abs(a - b) for a, b in zip(X, X[1:])]))

if len(lst) == 1 and lst[0] == 1:
  print('T')
else:
  print('F')