read_line.to_i.times do
  n = read_line.to_i64
  if n == 0
    puts 0
    next
  end
  ans = 0i64
  mul = 1i64
  m = n
  while m >= 0
    ans += mul
    mul *= m
    m -= 1
    mul %= 10
    if mul == 0
      break
    end
  end
  puts ans % 10
end