bracket_algorithm.rb

require 'rubygems'
require 'fattr'
require 'open-uri'
require 'singleton'
require 'enumerator'

class Team
  attr_accessor :seed, :team
  def initialize(team,seed)
    @seed, @team = seed,team
  end
  def pom
    Pom.instance.ratings[team]
  end
  def to_s
    "##{seed} #{team} (#{pom})"
  end
end

class Pom
  include Singleton
  fattr(:html) { open("http://kenpom.com") { |f| f.read } }
  fattr(:team_lines) do
    html.to_a.select { |x| x.strip =~ /^\d+ <a/ }
  end
  fattr(:ratings) do
    team_lines.inject({}) do |h,ln|
      team = ln.scan(/>(.*?)<\/a>/).flatten.first.downcase.gsub(/\./,"")
      rating = ln.scan(/\d+-\d+ +(\.\d+) /).flatten.first.to_f
      h.merge(team => rating)
    end
  end
end

class Game
  attr_accessor :teams
  def initialize(teams)
    @teams = teams.sort_by { |x| x.seed }
  end
  fattr(:high) { teams.first }
  fattr(:low) { teams[1] }
  def upset?
    low.team == winner.team
  end
  def factor
    (high.seed == low.seed) ? 0.0 : 0.0085
  end
  def winner
    (high.pom > low.pom + factor) ? high : low
  end
  def to_s
    teams.join(" vs ") + ", Winner: #{winner.team} " + (upset? ? "(UPSET)" : "")
  end
end
    
class Tourney
  attr_accessor :teams
  fattr(:teams) do
    seeds = [1,16,8,9,5,12,4,13,6,11,3,14,7,10,2,15] * 4
    $teams.split(",").zip(seeds).map do |x,seed|
      Team.new(x.strip,seed)
    end
  end
  fattr(:games) { [] }
  def run!
    while games.size < 63
      winners = []
      Enumerable::Enumerator.new(teams).each_slice(2) do |ts|
        g = Game.new(ts)
        winners << g.winner
        self.games << g
      end
      @teams = winners
    end
  end
end

$teams = "louisville,morehead st,ohio st,siena,utah,arizona,wake forest,cleveland st,west virginia,dayton,kansas,north dakota st,boston college,southern california,michigan st,robert morris,connecticut,chattanooga,brigham young,texas a&m,purdue,northern iowa,washington,mississippi st,marquette,utah st,missouri,cornell,california,maryland,memphis,cal st northridge,pittsburgh,east tennessee st,oklahoma st,tennessee,florida st,wisconsin,xavier,portland st,ucla,virginia commonwealth,villanova,american,texas,minnesota,duke,binghamton,north carolina,radford,louisiana st,butler,illinois,western kentucky,gonzaga,akron,arizona st,temple,syracuse,stephen f austin,clemson,michigan,oklahoma,morgan st"

t = Tourney.new
t.run!
t.games.each { |x| puts x }
puts "Upsets: " + t.games.select { |x| x.upset? }.size.to_s