cnn.rb

require 'json'

class CNN
  #parameter
  P = 0.75
  REPEAT = 200

  def initialize
    @nodes = [{"name" => 0}]
    @links = []
    @potential_links = []
  end

  def create
    node_no = 0
    REPEAT.times do |i|
      rand = rand()
      if rand <= P
        connect_node = (@nodes.size == 1) ? 0 : rand(@nodes.size - 1)
        @nodes.push({"name" => node_no + 1})
 
        if @links.size > 1
          @links.each do |link|
            if link['source'] == connect_node
              @potential_links.push({"source" => node_no + 1, "target" => link['target']})
            elsif link['target'] == connect_node
              @potential_links.push({"source" => node_no + 1, "target" => link['source']})
            end
          end
        end
        @links.push({"source" => node_no + 1, "target" => connect_node})
        node_no += 1
      else
        if @potential_links.size > 0
          link = (@potential_links.size == 1) ? @potential_links[0] : @potential_links[rand(@potential_links.size - 1)]
          @links.push(link)
          @potential_links.delete(link)
        end
      end
    end

    puts JSON.generate({"nodes" => @nodes, "links" => @links})
  end
end

c = CNN.new
c.create