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Welcome to Sudoku Explainer

Sudoku Explainer (SE) is primarily a Java (Swing) graphical user interface (GUI). It started life as DIUF Sudoku Explainer by Nicolas Juillerat. After reading Bernhard Hobigers review of SE I downloaded the latest version HoDoKu at the time (now superceeded) and cannibalised (pun intended) many of Bernhards solvers to bring SE's Sudoku solving techniques a-bit-more up-to-date.

DIUF Sudoku Explainer solved absolutely ANY (and then some) Sudoku puzzle, so I made it fast (and I mean seriously fast: I worked on government GIS server apps so I can dance by the record machine). HoDoKu offers a much more accurate assessment of the difficulty of "mid-level" Sudoku puzzles. So wouldn't it be nice if we could have the features of both? My solution was to add many of Bernhards hinters to DIUF Sudoku Explainer. Many are outright "boosted" but some are still "borrowed" directly from HoDoKu (included). Several minor changes were required to make HoDoKu work nicely within SE.

The coding style is "awkward". Because much of the code is intended to execute as quickly as possible there is little weight given to maintainability: so the low-level code is low-level, repeated, repeated, repetative, ugly, awkward, tricky, and damned near impossible for any other human being to change. Basically, you need to know what you need to change to change anything, and the way noobs learn what needs changing is to change it; so SE is snaphooed by it's own quick-full-ness. Sigh. The top-level code is "fairly standard" Swing app, but dig-down a few levels and you find custom collections (because the JAPI collections are a bit slow Redge. It's under the bonnet son) and parallel arrays, and precalculated tables, and basically every-other time-saving trick programmers have invented over the last 75 years to expedite s__t. No excuses: It's a PIG! But it's a fast pig! Think Piggy in a pink mini. Now staple an F1 to her back.

The primary intended audience for SE is other enthusiasts. "Normal people" can use SE to get an explanation of a Sudoku puzzle they found in a book, but they won't grow half-a-chub on the codez. It's fellow programmers, and there ideas, which interest me.

The wiki uses Markdown syntax.

Project Members:

• keith corlett (admin)