gistfile1.rb

class WordDictionary

  def initialize(dictionary_filename = '/usr/share/dict/words')
    @words = File.readlines(dictionary_filename)
    @words = @words.collect { |word| word.strip } # File.readlines preserves the newlines at the end of the line
  end

  def words_with_five_vowels_in_ascending_order
    @words.select { |word| word.count('aeiou') == 5 && word =~ /.*?[aA].*?[eE].*?[iI].*?[oO].*?[uU].*?/ }
  end

  def words_at_least_six_characters_with_letters_in_ascending_order
    # words have to be normalized to the same capitalization, duplicate chars removed, and then sorted.
    @words.select { |word| word.length >= 6 && word.downcase == word.downcase.squeeze.chars.sort.join }
  end

end

dictionary = WordDictionary.new

puts '1. Find all the words in a dictionary that contain exactly five vowels (a, e, i, o and u) in ascending order.'
puts dictionary.words_with_five_vowels_in_ascending_order.join("\n")

#=> abstemious
#=> abstemiously
#=> abstentious
#=> acheilous
#=> acheirous
#=> acleistous
#=> affectious
#=> annelidous
#=> arsenious
#=> arterious
#=> bacterious
#=> caesious
#=> facetious
#=> facetiously
#=> fracedinous
#=> majestious

puts '2. Find all the words in a dictionary of length at least six that contain letters in strictly ascending alphabetical order.'
puts dictionary.words_at_least_six_characters_with_letters_in_ascending_order.join("\n")

#=> abdest
#=> acknow
#=> Adelops
#=> adipsy
#=> agnosy
#=> almost
#=> befist
#=> behint
#=> beknow
#=> bijoux
#=> biopsy
#=> chintz
#=> dehors
#=> dehort
#=> Deimos
#=> deinos
#=> dimpsy
#=> egilops
#=> ghosty