T = int(input())
X = [int(input()) for i in range(T)]

for i in range(T):
	if i == 0:
		ans = abs((X[i] - 0))
		print('絶対値',ans,X[i])
	else:
		ans = abs((X[i] - X[i-1]))
		print('絶対値',ans,X[i])

	if ans == 1:
		pass
	else:
		print('F')
		break

if i == T-1:
	print('T')