solve wordle puzzle

solve_wordle.rb

#!/usr/bin/ruby

# sample.
# {
#   "q" => 0.00187529,
#   "j" => 0.00309423,
#   "z" => 0.00337553,
#   "x" => 0.00407876,
#   "v" => 0.0114393,
#   "w" => 0.0173465,
#   "f" => 0.0193624,
#   "k" => 0.0195499,
#   "g" => 0.0232536,
#   "b" => 0.0241444,
#   "h" => 0.0272386,
#   "y" => 0.0273793,
#   "m" => 0.0281763,
#   "p" => 0.032677,
#   "c" => 0.0332865,
#   "u" => 0.0349742,
#   "d" => 0.0427567,
#   "n" => 0.0466948,
#   "t" => 0.055368,
#   "i" => 0.0560713,
#   "l" => 0.0579466,
#   "o" => 0.0627754,
#   "r" => 0.067745,
#   "a" => 0.0855602,
#   "s" => 0.106892,
#   "e" => 0.106939,
# }
def create_character_frequency(words)
  freq = {}
  total = 0

  words.each do |word|
    word.split("").each do |c|
      freq[c] ||= 0
      freq[c] += 1
      total += 1
    end
  end

  freq.keys.each do |c|
    freq[c] = freq[c].to_f/total
  end

  return freq
end

def create_word_to_frequency_list(words, character_frequency)
  word2freq_list = words.map do |it|
    characters = it.split("")
    f = characters.map do |x|
      character_frequency[x]
    end
    [it,f.sum]
  end.sort do |a,b| 
    b[1] - a[1]
  end

  return word2freq_list
end

def answer_response(answer, input)
  result = input.map{|x| -1}
  answer_hash = answer.reduce({}) {|h,x| h[x] ||= 0; h[x] += 1; h}

  result = input.size.times.map do |i|
    a = answer[i]
    e = input[i]
    if a == e && answer_hash[e] > 0 then
      answer_hash[e] -= 1
      1
    else
      result[i]
    end
  end

  result = input.size.times.map do |i|
    a = answer[i]
    e = input[i]
    if a != e && answer_hash.key?(e) && answer_hash[e] > 0 then
      answer_hash[e] -= 1
      0
    else
      result[i]
    end
  end

  return result
end

def select_distinct_word(word2freq_list) 
  for word, freq in word2freq_list
    characters = word.split("")
    h={}
    is_distinct = true

    characters.each do |c|
      h[c] ||=0
      h[c] +=1

      if h[c] > 1
        is_distinct = false
        break
      end
    end

    if is_distinct
      return word
    end
  end

  word2freq_list[0][0]
end

def solve(answer, word2freq_list, max_try)
  answers = answer.split("")

  for try in 0...max_try do

    if word2freq_list.size <= 0
      return -1 
    end

    input = select_distinct_word(word2freq_list)
    inputs = input.split("")
    ans = answer_response(answers, inputs)
    return try if ans.all?(1)
    word2freq_list = word2freq_list.delete_if {|x| x[0] == input }

    inputs.each.with_index do |e, i|
      if ans[i] == 1 then
        word2freq_list = word2freq_list.filter {|w,f| w[i] == inputs[i]}
      elsif ans[i] == 0 then
        word2freq_list = word2freq_list.filter {|w,f| w.include?(inputs[i]) && w[i] != inputs[i]}
      else ans[i] == -1
        is_single = inputs.count{|x| x == inputs[i]} == 1
        if is_single then
          word2freq_list = word2freq_list.filter {|w,f| !w.include?(inputs[i])}
        end
      end
    end
  end

  return -1
end


def solve_all(words, word2freq_list, max_try)
  words.map do |word|
    result = solve(word, word2freq_list.clone, max_try)
    puts "#{word}\t#{result}"
  end
end


# MAIN

if ARGV.size <= 0
  puts <<__USAGE__
Usage:

  ruby solve_wordle.rb <word_list_txt> <word>?

Example:

  Solve all words 
    ruby solve_wordle.rb 5words.txt

  Solve specific word
    ruby solve_wordle.rb 5words.txt apple

Example of word list txt file:

  apple
  arrow
  bolts
  ...

Word sets reference:

  http://www.mieliestronk.com/wordlist.html

__USAGE__
  exit 1
end

WORDLIST_FILE = ARGV[0]
MAX_TRY = 20
words = File.read(WORDLIST_FILE).chomp.split("\n").map{|x| x.chomp}
character_frequency = create_character_frequency(words)
word2freq_list = create_word_to_frequency_list(words, character_frequency)

if ARGV.size > 1
  target_word = ARGV[1]
  puts solve(target_word, word2freq_list, 20)
else
  solve_all(words, word2freq_list, 20)
end