# import sys; input = sys.stdin.buffer.readline
# sys.setrecursionlimit(10**7)
from collections import defaultdict
con = 10 ** 9 + 7; INF = float("inf")

def getlist():
	return list(map(int, input().split()))

#処理内容
def main():
	T = int(input())
	x = 0
	for i in range(T):
		X = int(input())
		if abs(X - x) != 1:
			print("F")
			return
		x = X

	print("T")


if __name__ == '__main__':
	main()