def combine_anagrams(words)
  
  return nil if(words == [])
  result = []
  for i in 0 .. words.length-1
    array = []
    for j in 0 .. words.length-1
      array << words[j] if(words[i].split("").sort.join.downcase == words[j].split("").sort.join.downcase)
    end
    result << array
  end
  
  return result.uniq!
end

ex = ['cars', 'for', 'potatoes', 'racs', 'four', 'scar', 'creams', 'scream'] 
puts combine_anagrams(ex)