Category Archives: sudocue.net
Javascript
I’m still here…
A new interesting daytime job is eating away a lot of my time. 55 hours each week. Eat-sleep-family consumes another 70 hours. Producing the daily and weekly puzzles takes about 4 hours per week. Moderating 4 forums and keeping up with 3 others and keeping Sudopedia tidy takes 14 hours per week. That leaves 25 hours to do some Sudoku-related programming and website improvements. Choices need to be made.
The Lite page on SudoCue.net now has a Javascript helper. This gives me some hands-on experience with Javascript (needed for my daytime job) and it reduces traffic, because players do not need to make server roundtrips to check the results, add pencilmarks or apply filters. Given enough time, I could write a complete solver in Javascript. Interesting thought.
Other projects that I spent some time on:
Clueless Helper now supports the Samurai format, which is convenient for the many Samurai players.
Both a Samurai and a Clueless Explosion contest started on the website.
Lots of redesign work done on the SudoCue.net website. The soft blue-and-yellow theme is now consistent throughout the site. The pages and the tables look very smooth. To save bandwidth, the competition lists only show submission details for a single puzzle.
GattaiMaker
I spent the last week writing a new program which I called GattaiMaker. The name says it all. The program can generate overlapping Sudoku puzzles.
It is a major improvement over the CluelessMaker program which I used before for overlapping puzzles. CluelessMaker required me to generate a batch of puzzles with my regular Sudoku generator, which were glued together by CluelessMaker by relabeling the digits in the overlapping regions. Several configurations were tested and the best scoring combination was saved.
GattaiMaker can create any overlapping puzzle from scratch. It uses a DLX engine which is configured for the variant to be created. Diagonals are an option. The current version only supports global symmetry in every conceivable way, but the next version will also support local symmetry. A built-in solver can rate the puzzles. I’ve created it as a step-solver, so it does all occurrences of a specific type of move in a single step. Rating depends on the number of steps and the solving techniques used. This may obscure some advanced moves, but the overall difficulty of an overlapping puzzle is related to the number of alternative moves, which are measured by step counting. Finding the only possible single in a puzzle with 25 overlapping Sudokus is harder than spotting locked candidates when there are 20 present in the puzzle.
Internally, all solving techniques operate on the DLX data structures. I’ve never managed to do this before, but it works perfectly. No additional arrays, counters and masks are required. Every placement and elimination is implemented as a DLX operation.
The only format not supported yet is the Clueless Explosion, as the program cannot yet handle internally disjoint boxes. The regular Clueless format is supported, as well as the new Windmill format and two Clueless types merged with Sumo and Shaolin, respectively.
For advertising, I posted several different puzzles on my website and various forums.
First daily Sudoku-X on the WWW
Since I implemented Sudoku-X in SudoCue, I was wondering where people would be able to find these puzzles on a regular basis. To my surprise: nowhere! Only websudoku.com has a weekly feature of variants, and Inertia only pretends to have them, leading you to their desktop program.
So I decided to run my batch generator for a while, and it came up with a wonderful series of puzzles, with various symmetries and a wide range in difficulty levels. I decided to focus on 2 difficulty levels, one for the beginners and one for the advanced players, keeping them both happy on my site.
Since all my puzzles are themed, I needed one for this new feature. X-Rays, X-Wings, X-Men and X-Files were amongst the candidates. Combining the puzzles with an archive made me choose X-Files, which happened to be problems that needed to be solved. I’m still probing the theme, but there will be more wordplay in this arena. I’m full of ideas.
On a side note: The addition of regular puzzles and the rewriting of all the on-site documentation has resulted in a steady growth in visitors. This seems to have a snowball effect, because more and more people discover my site. It must have good pageranks in Google. Quality does pay off in the end.
Noblesse Oblige
Since Mike Barker has put my solving guide on top of his reference list in the sudoku player’s forum, I receive a lot of traffic from that reference. Thanks to Mike for this fine gesture.
I do not want let let all these new visitors down with a poor solving guide, so I started to rewrite it. The introduction is much longer now, with new topics covering sudoku history, an extended symmetry topic, minimal puzzles, known sudoku controversies and lots of explanation of the terminology. It almost reads like a book.
I replaced all the images, using a white cell background in stead of the typical SudoCue beige. The pictures are now better integrated with the text.
All the text on specific techniques has been rewritten and expanded, giving several examples and clear pictures. The list of techniques now includes hidden subsets, X-Wing, Swordfish & Jellyfish, and a very nice introduction to strong pairs and coloring. More will be added soon.
Ah yes, and I started BUG week.
Website Improvements
I have done a major overhaul of the main website. It has become rather messy with all the new additions. I now streamlined the design. Hope this attracts more visitors.
One of the improvements is a fully automated news archiver. I can upload any time anywhere a news item I deem worthy for the site, and indicate how long it will be on the front page. Anything that runs out-of-date is immediately placed in the news archive. The ‘read more…’ option is also a cool addition, saving space on the main page.
Clueless specials are now fully database driven. I can upload them straight from the CluelessMaker program.
Hanidoku will also be published in print, somewhere in September.
A privacy policy and copyright notice were added to the site.
The site is now validated for html 4.01, css and rss. Dunno if anyone cares, but it provides at least a minimum level of website code quality.
The sudoku solving guide has by far become the most popular page on the site. I’ve rewritten large portions, so it has a better consistency, smoother language and nicer pictures.
The easier level sudokus that I published on www.sudokuplaats.nl are now also published on the main site. This keeps beginners on the site a little longer.
Tips and no tips
A post about tips.
I have been writing solving tips for killer sudokus on a new page in this blog. Eventually, these tips must be placed on my main website, but as long as I am writing them, I will post them here in the blog.
I have a donate button on my site for 3 months now. So far, I have received 1 donation, with more than 300 site visits each day, 9000 SudoCue downloads and more than 400 SumoCue downloads. I planned to drop the Google ads as soon as the tips were higher than the ad income. Alas!
The Clueless Days
Sometimes I feel clueless myself.
The first of these monster puzzles were meant as an experiment. People jumped on it and wanted more and more. Creating these puzzles manually involves some risk. You have a shot at it and when it can be solved by 10 instances of SudoCue, then it should be OK. Difficulty can only be determined by testing. Because that takes such a long time, I tend to approve anything that passes the test, no matter how difficult.
Now I have CluelessMaker. It accepts 9 template-generated puzzles and a solution as input, maps the 9 puzzles to the central solution, and solves the whole thing in a fraction of a second. It counts naked/hidden singles, line-box interactions and naked/hidden subsets. More techniques will be built into it, but I can manually assess an almost solved clueless to see what is needed to complete it. If it’s a fair technique, I’ll let it pass.
What worries me, is that players no longer fancy the ‘regular’ sudokus. They want more and more clueless specials. If have made 4 by hand, the rest will be machine made, and more reliable.
Also had some fun on the player’s forum with the superior and inferior threads.
Clueless the Sequel
I have managed to construct another Clueless Special. It took some time to build this one, because the diamonds template does not have a lot of room to play with. I had to change 3 of the 9 puzzles to ensure they have a unique solution with the center box filled.
When I tested the complete puzzle, it turned out to be extremely difficult, but solvable with a single solution. I wonder how many people will manage to solve it. It takes a lot of force to connect the dots in this one.
My hosting company www.mijndomein.nl is doing some maintenance that they think is best done at midnight. That is the time that all the addicts come to look for a new Nightmare. I hope they are ready now, because for me this is becoming a nightmare. Too many sites now depend on my puzzles.
Free Hosting Satellites
With free hosting, it is possible to set up a few sites in a short amount of time. I was still collecting links for sudokustart and sudokuplaats, when I stumbled on a few free hosting companies. Daily sudokus are now shown on a couple of new sites, and links to sudocue.net have been added.
A Dutch user guide for SudoCue was long overdue, and in fact the only thing missing on sudokuplaats. It is now there.
Still programming and planning SudokuStart. This site must have a good launch, so I’ll give it a bit extra time.
Finally had contact with Milo, the site admin of the sudoku programmers forum. I’m now a moderator for the forum, which allows me to take care of the forum, by adding sticky topics and remove rubbish.
Another candidate for sudocue daily syndication, and received an interesting business proposal. The activities seem to produce results now.