n = int(input())

if n == 1:
    print('F')
else:


    ls = []
    for i in range(n):
        ls.append(int(input()))

    LS = []
    for i in range(n-1):
        LS.append(abs(ls[i+1] - ls[i]))

    if len(LS) == LS.count(1):
        print("T")
    else:
        print("F")