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

# Check the first position
if abs(X[0]) != 1:
    print("F")
else:
    valid = True
    for i in range(1, T):
        if abs(X[i] - X[i-1]) != 1:
            valid = False
            break
    print("T" if valid else "F")