A wordle-style puzzle the length of the novel Moby-Dick, roughly 214,575 words or 1,149,269 characters long. Since it would take quite a while for a human to solve, we let a computer solve it instead and stream its guesses to the webpage; it's typically able to win in around 24 guesses. Although the solution is fixed, the computer's strategy is non-deterministic, so reloading the page will (usually) show a different sequence of guesses.

The computer uses the strategy described in this paper, which wins in a bounded number of guesses for puzzles of length ω_{0}. Maybe a bit overkill for a mere 1.1 million characters, but at least it was pretty easy to code.

Solutions are generated offline (it takes my laptop a few minutes to generate one) and loaded incrementally by the visualizer. The solver is written in Haskell and uses a simple depth-first search (by way of the List monad) for coming up with valid guesses. The visualization is written in Elm and was much more of a pain in the ass to get right than the solver. The source code for both is available here.

The delightful Fantasque Sans.