generate some massachusetts town names

towns.rb

#!/usr/bin/env ruby

class WordMarkov
  def initialize(data=[])
    @nexts = {}
    @initials = []
    data.each do |word|
      chars = word.split('')
      @initials << chars[0..1]
      chars[0..-3].each_with_index do |char, i|
        key = chars[i..i+1].join
        val = chars[i + 2]
        @nexts[key] ? @nexts[key] << val : @nexts[key] = [val]
      end
      key = chars[-2..-1].join
      val = nil
      @nexts[key] ? @nexts[key] << val : @nexts[key] = [val]
    end
  end
  
  def word
    out = @initials[rand(@initials.length)].dup
    while out[-1] != nil
      possibles = @nexts[out[-2..-1].join]
      out << possibles[rand(possibles.length)]
    end
    out.pop
    return out.join
  end
  
  def possible?(word)
    chars = word.split('')
    while chars.length > 2
      if @nexts[chars[0..1].join].include? chars[2]
        chars.shift
      else
        return false
      end
    end
    return true
  end
end

if __FILE__ == $0
  towns = ['Abington', 'Acton', 'Acushnet', 'Adams', 'Agawam', 'Alford', 'Amesbury', 'Amherst', 'Andover', 'Aquinnah', 'Arlington', 'Ashburnham', 'Ashby', 'Ashfield', 'Ashland', 'Athol', 'Attleboro', 'Auburn', 'Avon', 'Ayer', 'Barnstable', 'Barre', 'Becket', 'Bedford', 'Belchertown', 'Bellingham', 'Belmont', 'Berkley', 'Berlin', 'Bernardston', 'Beverly', 'Billerica', 'Blackstone', 'Blandford', 'Bolton', 'Boston', 'Bourne', 'Boxborough', 'Boxford', 'Boylston', 'Braintree', 'Brewster', 'Bridgewater', 'Brimfield', 'Brockton', 'Brookfield', 'Brookline', 'Buckland', 'Burlington', 'Cambridge', 'Canton', 'Carlisle', 'Carver', 'Charlemont', 'Charlton', 'Chatham', 'Chelmsford', 'Chelsea', 'Cheshire', 'Chester', 'Chesterfield', 'Chicopee', 'Chilmark', 'Clarksburg', 'Clinton', 'Cohasset', 'Colrain', 'Concord', 'Conway', 'Cummington', 'Dalton', 'Danvers', 'Dartmouth', 'Dedham', 'Deerfield', 'Dennis', 'Dighton', 'Douglas', 'Dover', 'Dracut', 'Dudley', 'Dunstable', 'Duxbury', 'East Bridgewater', 'East Brookfield', 'East Longmeadow', 'Eastham', 'Easthampton', 'Easton', 'Edgartown', 'Egremont', 'Erving', 'Essex', 'Everett', 'Fairhaven', 'Fall River', 'Falmouth', 'Fitchburg', 'Florida', 'Foxborough', 'Framingham', 'Franklin', 'Freetown', 'Gardner', 'Georgetown', 'Gill', 'Gloucester', 'Goshen', 'Gosnold', 'Grafton', 'Granby', 'Granville', 'Great Barrington', 'Greenfield', 'Groton', 'Groveland', 'Hadley', 'Halifax', 'Hamilton', 'Hampden', 'Hancock', 'Hanover', 'Hanson', 'Hardwick', 'Harvard', 'Harwich', 'Hatfield', 'Haverhill', 'Hawley', 'Heath', 'Hingham', 'Hinsdale', 'Holbrook', 'Holden', 'Holland', 'Holliston', 'Holyoke', 'Hopedale', 'Hopkinton', 'Hubbardston', 'Hudson', 'Hull', 'Huntington', 'Ipswich', 'Kingston', 'Lakeville', 'Lancaster', 'Lanesborough', 'Lawrence', 'Lee', 'Leicester', 'Lenox', 'Leominster', 'Leverett', 'Lexington', 'Leyden', 'Lincoln', 'Littleton', 'Longmeadow', 'Lowell', 'Ludlow', 'Lunenburg', 'Lynn', 'Lynnfield', 'Malden', 'Manchester-by-the-Sea', 'Mansfield', 'Marblehead', 'Marion', 'Marlborough', 'Marshfield', 'Mashpee', 'Mattapoisett', 'Maynard', 'Medfield', 'Medford', 'Medway', 'Melrose', 'Mendon', 'Merrimac', 'Methuen', 'Middleborough', 'Middlefield', 'Middleton', 'Milford', 'Millbury', 'Millis', 'Millville', 'Milton', 'Monroe', 'Monson', 'Montague', 'Monterey', 'Montgomery', 'Mount Washington', 'Nahant', 'Nantucket', 'Natick', 'Needham', 'New Ashford', 'New Bedford', 'New Braintree', 'New Marlborough', 'New Salem', 'Newbury', 'Newburyport', 'Newton', 'Norfolk', 'North Adams', 'North Andover', 'North Attleborough', 'North Brookfield', 'North Reading', 'Northampton', 'Northborough', 'Northbridge', 'Northfield', 'Norton', 'Norwell', 'Norwood', 'Oak Bluffs', 'Oakham', 'Orange', 'Orleans', 'Otis', 'Oxford', 'Palmer', 'Paxton', 'Peabody', 'Pelham', 'Pembroke', 'Pepperell', 'Peru', 'Petersham', 'Phillipston', 'Pittsfield', 'Plainfield', 'Plainville', 'Plymouth', 'Plympton', 'Princeton', 'Provincetown', 'Quincy', 'Randolph', 'Raynham', 'Reading', 'Rehoboth', 'Revere', 'Richmond', 'Rochester', 'Rockland', 'Rockport', 'Rowe', 'Rowley', 'Royalston', 'Russell', 'Rutland', 'Salem', 'Salisbury', 'Sandisfield', 'Sandwich', 'Saugus', 'Savoy', 'Scituate', 'Seekonk', 'Sharon', 'Sheffield', 'Shelburne', 'Sherborn', 'Shirley', 'Shrewsbury', 'Shutesbury', 'Somerset', 'Somerville', 'South Hadley', 'Southampton', 'Southborough', 'Southbridge', 'Southwick', 'Spencer', 'Springfield', 'Sterling', 'Stockbridge', 'Stoneham', 'Stoughton', 'Stow', 'Sturbridge', 'Sudbury', 'Sunderland', 'Sutton', 'Swampscott', 'Swansea', 'Taunton', 'Templeton', 'Tewksbury', 'Tisbury', 'Tolland', 'Topsfield', 'Townsend', 'Truro', 'Tyngsborough', 'Tyringham', 'Upton', 'Uxbridge', 'Wakefield', 'Wales', 'Walpole', 'Waltham', 'Ware', 'Wareham', 'Warren', 'Warwick', 'Washington', 'Watertown', 'Wayland', 'Webster', 'Wellesley', 'Wellfleet', 'Wendell', 'Wenham', 'West Boylston', 'West Bridgewater', 'West Brookfield', 'West Newbury', 'West Springfield', 'West Stockbridge', 'West Tisbury', 'Westborough', 'Westfield', 'Westford', 'Westhampton', 'Westminster', 'Weston', 'Westport', 'Westwood', 'Weymouth', 'Whately', 'Whitman', 'Wilbraham', 'Williamsburg', 'Williamstown', 'Wilmington', 'Winchendon', 'Winchester', 'Windsor', 'Winthrop', 'Woburn', 'Worcester', 'Worthington', 'Wrentham', 'Yarmouth']
  w = WordMarkov.new(towns)
  100.times do
    word = w.word
    puts word unless towns.include? word
  end
end