class Hamster::Vector

def initialize(items=[].freeze)
  items = items.to_a
  if items.size <= 32
    items = items.dup.freeze if !items.frozen?
    @root, @size, @levels = items, items.size, 0
  else
    root, size, levels = items, items.size, 0
    while root.size > 32
      root = root.each_slice(32).to_a
      levels += 1
    end
    @root, @size, @levels = root.freeze, size, levels
  end
end