Anagrams Ruby Exercise

anagrams.rb

#* Write a Ruby method group_anagrams that takes an array of strings as input 
#* and groups the anagrams together. 
#* Anagrams are words or phrases formed by rearranging the letters of another.

def group_anagrams(words)
  groups = {}
  words.each_with_index do |word, index|
    sorted_word = word.chars.sort.join
    if groups[sorted_word].nil?
      groups[sorted_word] = [word]
    else
      groups[sorted_word] << word
    end
  end
  groups
end

words = ['cat', 'tea', 'eat', 'ate', 'bat', 'eattt', 'tac', 'cct']

puts group_anagrams(words)