An automated solving library for the popular game: Wordle
See the docs.
0.2.0
Enable parallelization with Rayon
Parallelize key parts of MaxEliminationsScorer::new
MaxComboEliminationsScorer::new
Parallelize MaxScoreGuesser::select_next_guess
and ::select_top_n_guesses
Make WordScorer::score_word
take &self
instead of &mut self
MaxComboEliminationsScorer
to improve its resultsDifferent guessing algorithms have been benchmarked against a few word lists:
wordle-answers.txt
: this list is the all answer words from
Wordle before it was purchased by the New
York Times.
improved-words.txt
: this list combines all 5-letter words from the Corncob list of more than
58,000 English words, the MIT 10000 English words
list, and any remaining Wordle answer words. This
is often used instead of the full wordle word list, as many allowed Wordle words seem to be
somewhat nonsensical.
Most algorithms have been benchmarked against the whole improved words list. Some algorithms run in two configurations:
PossibleWords
, i.e. only guessing words that are still possible. This is
equivalent to Wordle's "hard" mode.AllUnguessedWords
, including words that can't be the answer. This is usually
better as the algorithms are able to eliminate more words faster.This selects randomly from the words that are still possible. It's a baseline worst-case selection. Any other algorithm should be better than this.
One sample benchmark:
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 106 | | 3 | 816 | | 4 | 1628 | | 5 | 1248 | | 6 | 518 | | 7 | 180 | | 8 | 67 | | 9 | 28 | | 10 | 7 | | 11 | 2 | | 12 | 1 |
Average number of guesses: 4.49 +/- 1.26
This is a fairly naive selector. It selects the word that maximizes the sum of the frequency of unique letters that have not yet been guessed.
GuessFrom::PossibleWords
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 137 | | 3 | 1264 | | 4 | 1831 | | 5 | 829 | | 6 | 321 | | 7 | 129 | | 8 | 57 | | 9 | 26 | | 10 | 6 | | 11 | 1 |
Average number of guesses: 4.16 +/- 1.22
GuessFrom::AllUnguessedWords
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 32 | | 3 | 1019 | | 4 | 2227 | | 5 | 1054 | | 6 | 228 | | 7 | 36 | | 8 | 5 |
Average number of guesses: 4.12 +/- 0.87
This selects the word that maximizes a score, based on both the presence and the the location of that letter in the possible words. The score is computed for each letter and then summed. Each letter is scored as follows.
For each letter, score:
If this letter is completely new:
If this letter has not yet been scored in this word:
1 point for every possible word with this letter in the same place.
1 point for every possible word with this letter in another place.
Else:
1 point for every possible word with this letter in the same place.
GuessFrom::PossibleWords
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 180 | | 3 | 1442 | | 4 | 1838 | | 5 | 722 | | 6 | 259 | | 7 | 101 | | 8 | 41 | | 9 | 13 | | 10 | 3 | | 11 | 1 | | 12 | 1 |
Average number of guesses: 4.00 +/- 1.15
GuessFrom::AllUnguessedWords
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 114 | | 3 | 1558 | | 4 | 2023 | | 5 | 633 | | 6 | 180 | | 7 | 62 | | 8 | 22 | | 9 | 7 | | 10 | 2 |
Average number of guesses: 3.90 +/- 0.99
This selects the word that is expected to eliminate approximately the most other words. For each letter, the expected number of eliminations is computed for each possible state:
So for example, with the words ["could", "match", "coast"]
, these would be computed as follows
for the letter c
in could
:
match
is removed, so: 1 * (2/3)could
and coast
are removed, so: 2 * (1/3)These per-letter expectations are then summed together to get the expectation value for the word.
Approximating the expected eliminations in this way is cheap to compute, but slightly less accurate,
and therefore less effective, than using the precise counts computed by MaxEliminationsScorer
.
GuessFrom::PossibleWords
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 180 | | 3 | 1415 | | 4 | 1843 | | 5 | 734 | | 6 | 262 | | 7 | 104 | | 8 | 41 | | 9 | 14 | | 10 | 6 | | 11 | 1 | | 12 | 1 |
Average number of guesses: 4.02 +/- 1.16
GuessFrom::AllUnguessedWords
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 72 | | 3 | 1303 | | 4 | 2507 | | 5 | 664 | | 6 | 52 | | 7 | 3 |
Average number of guesses: 3.85 +/- 0.72
This probabilistically calculates the expectation value for how many words will be eliminated by each guess, and chooses the word that eliminates the most other guesses. This is relatively expensive to compute, so it precomputes as much as possible when the scorer is first created. On my machine, constructing the scorer with the improved-words list takes about 350ms, but this enables each subsequent game to be played in about 27ms.
GuessFrom::PossibleWords
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 180 | | 3 | 1452 | | 4 | 1942 | | 5 | 666 | | 6 | 220 | | 7 | 93 | | 8 | 33 | | 9 | 10 | | 10 | 4 | | 11 | 1 |
Average number of guesses: 3.95 +/- 1.10
GuessFrom::AllUnguessedWords
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 53 | | 3 | 1426 | | 4 | 2635 | | 5 | 468 | | 6 | 19 |
Average number of guesses: 3.78 +/- 0.65
When benchmarked against the wordle answers using the improved-words list as a word bank, the results are:
| Num guesses | Num games | | ----------- | --------- | | 2 | 23 | | 3 | 777 | | 4 | 1364 | | 5 | 148 | | 6 | 3 |
Average number of guesses: 3.71 +/- 0.60 (time taken: 20.6 seconds)
This extends the MaxEliminationsScorer
to choose the word that should maximize the number of
eliminated words across the next two guesses, as long as there are more than a specifiable limit
of possible words. We'll call this the combo limit
. Once there are fewer than the combo limit
possible words left, this falls back to the MaxEliminationsScorer
behavior.
The theory behind this scorer is that, since most words take at least 3 guesses, the scorer should
try to eliminate the most possible words collectively in the first two guesses. This could perform
differently from choosing the best individual word per round, as is done in
MaxEliminationsScorer
.
This is extremely expensive to compute, as it scales in approximately O(nn
is the number of words in the word bank. Similar to MaxEliminationScorer
, it
precomputes the first guess, which takes about 40 minutes for ~4600 words, and solving a single word then takes about 10 seconds on average (with wide variance, largely depending on how many words were eliminated, and what combo_limit
you are using).
Combo limit: 256 and GuessFrom::AllUnguessedWords:
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 148 | | 3 | 1500 | | 4 | 2041 | | 5 | 619 | | 6 | 180 | | 7 | 73 | | 8 | 27 | | 9 | 9 | | 10 | 2 | | 11 | 2 |
Average number of guesses: 3.91 +/- 1.03
Combo limit: 256 and GuessFrom::AllUnguessedWords:
| Num guesses | Num games | | ----------- | --------- | | 1 | 1 | | 2 | 59 | | 3 | 1392 | | 4 | 2753 | | 5 | 372 | | 6 | 25 |
Average number of guesses: 3.76 +/- 0.63 (time taken: 13 hours 10 minutes)
test bench_guess_random_improved_words ... bench: 134,544 ns/iter (+/- 13,317)
test bench_guess_random_wordle_words ... bench: 360,913 ns/iter (+/- 48,680)
test bench_unique_letters_improved_words ... bench: 1,572,994 ns/iter (+/- 516,087)
test bench_located_letters_improved_words ... bench: 1,575,697 ns/iter (+/- 512,853)
test bench_max_approximate_eliminations_improved_words ... bench: 1,595,036 ns/iter (+/- 839,135)
test bench_max_eliminations_scorer_precompute_improved_words ... bench: 404,998,819 ns/iter (+/- 7,069,306)
test bench_max_eliminations_scorer_with_precomputed_improved_words ... bench: 10,699,991 ns/iter (+/- 10,244,686)
Precompute on improved words takes roughly: 41 minutes (guess from all words) or 3.5 minutes (guess from possible words) Solving a single word takes roughly: 10 seconds (guess from all words) or 0.16 seconds (guess from possible words)