syracuse

syracuse.rb

class Syracuse < Struct.new(:initial, :chiffre, :altitude, :duree_vol, :success)

  HIGHER_THRESHOLD = 100000000000

  def initialize(chiffre)
    self.initial  = self.chiffre   = chiffre
    self.altitude = self.duree_vol = 0
  end

  def next
    with_backup do
      self.chiffre = chiffre.even? ?  chiffre / 2 : (chiffre * 3 ) + 1
    end
  end

  def with_backup(&block)
    self.altitude = chiffre if altitude < chiffre
    self.duree_vol = duree_vol + 1
    yield
  end

  def finished?
    return false unless duree_vol > 0
    return false unless [ HIGHER_THRESHOLD, 1 ].include? chiffre
    self.success = chiffre == 1 ? true : false 
  end
end

class Runner < Struct.new(:borne_sup)

  def go
    results = get_results

    max_duree_vol = results.max_by(&:duree_vol)
    max_altitude  = results.max_by(&:altitude)

    puts "duree vol max: #{ max_duree_vol.duree_vol }, chiffre: #{max_duree_vol.initial}"
    puts "altitude max: #{ max_altitude.altitude }, chiffre: #{max_altitude.initial}"
  end
  
  def get_results
    (1..borne_sup).map do |chiffre|
      
      syracuse = Syracuse.new(chiffre)

      syracuse.next until syracuse.finished?

      syracuse
    end
  end

end

Runner.new(1000).go