def fizzbuzz(n)
  count = 0
  # fizzbuzz
  (1..n).each do |i|
    if i % 3 == 0 && i % 5 == 0
      count += 4
      next
    elsif i % 3 == 0 || i % 5 == 0
      count += 2
      next
    end
  end
  count.to_i
end

input = $stdin.gets.to_i

puts fizzbuzz(input)