ぶどう問題。最後の方は明らかに力尽きている

gistfile1.rb

require 'set'

class Bunch
  def initialize(bunch1, bunch2 = nil)
    (bunch2 != nil) ? mergeBunch(bunch1, bunch2) : initValue(bunch1)
  end
  def initValue(value)
    @bunch1 = nil
    @bunch2 = nil
    @value = value
    @values = [value].to_set
    @rank = 1
  end
  def mergeBunch(bunch1, bunch2)
    @bunch1 = bunch1;
    @bunch2 = bunch2;
    @value = (bunch1.value - bunch2.value).abs
    @values = bunch1.values + bunch2.values
    @values.add(@value)
    @rank = bunch1.rank + 1
  end
  def check
    (@rank + 1) * @rank / 2 == @values.count
  end
  attr_accessor :bunch1, :bunch2, :value, :values, :rank
end

class Rank
  def initialize(bunchs)
    @bunchs = bunchs
  end
  def nextRank
    r = Rank.new(self.nextBunchs)
    (r.check) ? r : nil
  end
  def nextBunchs
    @bunchs[1..-1].inject([[], @bunchs[0]]){|s, b| [s[0] + [Bunch.new(s[1], b)], b] }[0]
  end
  def check
    @bunchs.inject(true) {|s, b| s && b.check}
  end
  attr_accessor :bunchs
end

class Grape
  def initialize(numbers)
    bunchs = numbers.map{|s| Bunch.new(s)}
    rank = Rank.new(bunchs)
    ranks = [rank]
    for i in (2..(numbers.count))
      rank = rank.nextRank
      if (rank != nil)
        ranks += [rank]
      else
        break
      end
    end
    if (ranks.count == numbers.count)
    	@ranks = ranks
    end
  end
  def print
    @ranks.map{|r| r.bunchs.map{|b| "#{b.value}"}.join(" ")}.join("\n")
  end
  attr_accessor :ranks
end

for i1 in 1..15
  for i2 in 1..15
    for i3 in 1..15
      for i4 in 1..15
        for i5 in 1..15
          g = Grape.new([i1, i2, i3, i4, i5])
          if (g.ranks != nil)
          	puts g.print
          end
        end
      end
    end
  end
end