n = gets.chomp!.to_i

def pokke(bis)
  tmp = 0
  count = 0
  pokebis = bis
  while pokebis > 1
    tmp += pokebis % 2
    pokebis /= 2
    pokebis += tmp
    tmp = 0
    count += 1
  end
  count
end

puts pokke(n)