num = gets.to_i
now = 0
for i in 1..num
    input = gets.to_i
    if i == 1 && input == 0 
	puts "F"
	break
    end
    if  (now - input).abs >= 2 || (now - input).abs == 0
        puts "F"
        break
    else
        now = input
    end
    if i == num && (now - input).abs <= 1 
	puts "T"
	break
    end
end
# your code goes here