T = int(input())
X = list(map(int, [input() for i in range(T)]))
flag = 1
if X[0] == 0:
    print('F')
else:
    while(flag==1):
        for i in range(T-1):
            if abs(X[i]-X[i+1]) != 1:
                flag = 0
                print('F')
                exit()
            elif i == T - 2:
                print('T')
                flag = 0