T = gets.to_i
Array = []
T.times { Array << gets.to_i }
#print(Array)
unless Array[0] =1 or Array[0] =-1
  hantei=1
 else
  hantei=0
end

for k in (0..(T-1))
  hantei=1  unless Array[k]-Array[k+1]=1
end
 
if hantei=0
  print("T")
else
  print("F")
end