Redwine's assignment, done in Ruby

hangmun.rb

all_words = File.open('dictionary.txt', 'r') {|f| f.each_line.map{|l|l.strip}.to_a }
all_words.reject! {|w| w.nil? || w == '' }

# --- prompt and initialise

candidates = []
while candidates.empty?
  print "Word length: "
  length = STDIN.gets.to_i
  if length <= 0 || (candidates = all_words.select {|w| w.length == length}).empty?
    puts "That's silly."
  end
end

correct = [nil] * length
used = {}

lives = 0
while lives <= 0
  print "Incorrect guesses: "
  lives = STDIN.gets.to_i
  if lives <= 0
    puts "That's silly."
  end
end

show_num = nil
while show_num.nil?
  print "Show number of possible words? [Y/N] "
  ans = STDIN.gets[0].downcase
  if ans == 'y'
    show_num = true
  elsif ans == 'n'
    show_num = false
  end
end

# --- game loop

while lives > 0
  puts ""
  puts "You have #{lives} incorrect guess#{lives == 1 ? '' : 'es'} left."
  puts "[\# word possible: #{candidates.length}]" if show_num
  puts "Word: #{correct.map{|c| c.nil? ? '_' : c}.join(' ')}"
  puts "Used letters: #{used.keys.sort.join(' ')}"
  print "Enter guess:  "
  char = STDIN.gets[0].downcase
  if char !~ /[a-z]/
    puts "That's not a letter."
  elsif used[char]
    puts "You've already tried #{char}."
  else
    used[char] = 1
    # Categories candidate words into families
    families = {}
    candidates.each do |word|
      template = word.tr "^#{char}", '-'
      families[template] ||= []
      families[template] << word
    end
    # Select a family (in this case, largest)
    family = families.max_by{|template, list| list.length }
    candidates = family[1]
    # Reward or Punishment
    if family[0].gsub('-', '') == ''
      puts "Sorry, there are zero."
      lives -= 1
    else
      puts "You guessed a letter correctly!"
      family[0].each_char.with_index do |char, idx|
        correct[idx] = char if char != '-'
      end
      # Maybe game over (in a good way?)
      break unless correct.find_index(nil)
    end
  end
end

puts "Game over"
puts "The word is #{candidates[rand candidates.length]}"

https://www.cs.wcupa.edu/rburns/Game/assignments/hw1/