n = gets.to_i
ys = gets.chomp.split.map(&:to_i)
left = ys.min
right = ys.max

1000.times do
  r1 = (left + left + right) / 3
  r2 = (left + right + right) / 3
  s1 = ys.map { |y| (y - r1).abs }.inject :+
  s2 = ys.map { |y| (y - r2).abs }.inject :+
  if s1 < s2
    right = r2
  else
    left = r1
  end
end

ans = 100000000000
(left..right).each do |r|
  s = ys.map { |y| (y - r).abs }.inject :+
  ans = [ans, s].min
end
p ans