Solrdle

Solr powered Wordle guesser. "so lord uhl"

Installation

• Start Solr and create a words collection:

$SOLR_HOME/bin/solr create -c words

• Index the five letter words into Solr:

$SOLR_HOME/bin/post -c words solr_docs.json

Usage

Word guesser

Given some guesses and Wordle supplied clues:

$ ruby word_guesser.rb "AUDIO ~xxxx" "BASIC ^~xxx" "PLAIN xx^xx" 
BRAKE
BRAVE

Solving for known answer

$ ruby grader.rb AROMA
AROMA :
ETUDE xxxxx
"ETUDE xxxxx" "BLOOM xx^x~"
"ETUDE xxxxx" "BLOOM xx^x~" "AMONG ^~^xx"
  Solved in 4 guesses

grader.rb starts with a known answer and picks possible solutions given known hints until solution matches.

Fetch all Wordle words and generate Solr docs

$ ruby solr_doc_gen.rb > solr_docs.json 

Examples

Example 1: SOLAR TONIC

For this first example, a larger (>15,000) list of words was used than necessary, before learning about Wordle's smaller list actually used. Compare this with Example 2 to see how much quicker a smarter, smaller dictionary works.

For this example, run these steps to have a larger word list index:

• Download words_alpha.txt from https://github.com/dwyl/english-words

• Extracted all five letter words from the words_alpha.txt file using (file contains carriage returns, so have to account for that):

cat words_alpha.txt | grep '^.....\r$' > five_letter_words.txt

• Now generate a Solr JSON data file:

ruby solr_doc_gen.rb > solr_docs.json

If you've already indexed the provided smaller word list, recreate the words by first deleting it with bin/solr delete -c words and recreate that collection and index the newly generated solr_docs.json as detailed above.

We start with the word SOLAR:

We now know that the second letter is O and that none of the letters S, L, A, nor R are in the solution. Using this information, we query Solr using these these filters:

• -({!terms f=letters_ss v=$exclude_letters})
• letter2_s:O

where $exclude_letters is S,L,A,R

there's 570 words that match this criteria (out of nearly 16,000 words in the word list used), from BOBBY to ZOWIE.

Glancing through the list and picking one of those words, TONIC, gives this new information:

We now know that I and C are also not in the solution as well, and we know that there is a T but not as the first letter and there's an N but not as the third letter. We add this information to our Solr filters:

• -letter1_s:T
• -letter3_s:N
• letters_ss:(T AND N)
• and we add I and C to $exclude_letters: S,L,A,R,I,C

After two rows we have only 6 possible words left: FOUNT, MOTON, MOUNT, NOBUT, NOTED, and NOTUM.

Let's give one of those non-obscure words a try, NOTED:

Oops still not there. With this new information our Solr filters are now:

• -({!terms f=letters_ss v=$exclude_letters})
• letter2_s:O
• -letter1_s:T
• -letter3_s:N
• letters_ss:(T AND N)
• -letter1_s:N
• -letter3_s:T
• with $excluded_filters set to S,L,A,R,I,C,E,D

Only two possible words left: FOUNT and MOUNT. One more Solr-educated guess: MOUNT:

Tada!

The full final Solr request is http://localhost:8983/solr/words/select?rows=9999&wt=csv&fl=id&q=*:*&fq=-({!terms%20f=letters_ss%20v=$exclude_letters})&exclude_letters=S,L,A,R,I,C,E,D&fq=letter2_s:O&fq=-letter1_s:T&fq=-letter3_s:N&fq=letters_ss:(T%20AND%20N)&fq=-letter1_s:N&fq=-letter3_s:T

Example 2: SOLAR TONIC with smaller dictionary

Using the provided word list of ~2,300 words, let's try the same first couple of guesses from Example 1. First SOLAR, which now yields 86 possible solutions. Next we guess TONIC, which narrows the possible solutions down to only one! We've found a match in three tries, after only two guesses.

The full Solr URL for to get to this solution is: http://localhost:8983/solr/words/select?rows=9999&xwt=csv&fl=id&q=*:*&fq=-({!terms%20f=letters_ss%20v=$exclude_letters})&exclude_letters=S,L,A,R,I,C&fq=letter2_s:O&fq=-letter1_s:T&fq=-letter3_s:N&fq=letters_ss:(T%20AND%20N)

How it works

solr_doc_gen.rb holds the key to how this works. Each word becomes a document in Solr, with the word itself being the unique id. Each letter of the word is indexed into positional fields: letter1_s..letter5_s so we can use the green lighted, exact position match information, to narrow down the possibilities. Additionally, each letter of the word is added individually to a "bag of letters", letters_ss, field allowing us to exclude the greyed out letters and include the "right letter wrong position" letters.

The *_s suffix is a single-valued string field in Solr, and *_ss is multivalued, using Solr's default schema.