From: SHINDO Motoaki <motoakira@...>
Date: 2008-07-22T20:51:42+09:00
Subject: Re: m order b-tree


On 2008/07/19, at 21:21, sngtnair84@gmail.com wrote:

> I need a ruby implementation of m-order B-tree, where m > 2.


I don't get you got some reply, so
I put my experimental code. would it work for you?

Yes(or Nope),
it's not the Tree of its children is the Tree-itself, but
is it your STRICT Requirements?

=== source follows (contains Kanji, see it in UTF-8)

class CommentTree

	def initialize(root)
		@root = root
		@last = root
		@changed = false
	end

	def root
		@root
	end
	alias top root
	def changed?
		@changed
	end
	def clear
		@changed = false
=begin
	as some trivial work-around, this method is here
=end
	end
	def seek(id)
		@root.seek(id)
	end
	
	def put(node)
		parent = seek(node.parent_num)
		if parent.nil? then nil
		else
			parent.put(node)
			@last = node
			@changed = true
			parent
		end
	end
	
	def remove(id, note)
		ruin = nil
		node = seek(id)
		if node.nil?
		else
			ruin = node.emptize(note)
			@changed = true
		end
		ruin
	end
	
	def each(&block)
		@root.each &block
	end
	def overview
		print 'Â¥n'
		@root.each { |node|
			print 'Â¥n'
			node.generation.times {print 'Â¥t'}
			print node.id
		}
		print 'Â¥n'
	end

	def entry(node)
		line =""
		node.generation.times {line += "&mdash;"}
		line += node.entry
		line += "<br>Â¥n"
	end
	def entries(cgi)
		lines = ""
		each { |node|
			lines += cgi.a({"href" => "./article.cgi?cueto=#{node.id}",
					"target" => "Article"}) { entry(node) }
		}
		cgi.p { lines }
	end
	
=begin	
	These methods are of imaginations, but I won't implement 'em
	def next(node)
	end
	def prev(node)
	end	
	
	def car
	end
	def cdr
	end
	
	def subtree(generation)
	end
	
	def leaf(serial)
	end
	def leaves
	end
=end
end

=== source ends


=============================
  ContextSwitcher

         Shindo  Motoakira
    <motoakira@mac.com>
=============================