Fifth in a series with puzzle solving tips. This time, with some advice on global constraints that arise in loop puzzles.

Some of you have asked why I don’t put “general tips” up before I post any puzzles. I find that learning how to solve puzzles is more interesting than reading how to do every single step. I won’t post a list of the top 20 Slitherlink patterns you should memorize, for example, on the rules and info page. Most of you would probably get more enjoyment figuring those out for yourself. But, after you’ve solved a challenge, I do like highlighting some of the things as constructor I tried to include, perhaps as a lesson for the future. This is what I will do this week with parity constraints for the Friday Masyu.

(more…)

We’re now halfway through what I’ve been calling the “introduction” phase of Grandmaster Puzzles, in which I introduce the majority of the genres I’ll be including in my next few books, both as author and as editor. After the “introduction” phase, there will be puzzles by some other talented puzzle constructors here. And I hope to have over half of the puzzles in The Art of Puzzles written by others, maybe even you. I’ll be sending a detailed contributor email out by the end of the week so if you haven’t contacted me yet with interest in writing puzzles for these projects, now is the time to do so.

After the discussion last week, I’ve decided to change my reported time standards a bit. First, “Grandmaster” will be introduced and will be equivalent to about where Master was set before, timed close to my best test-solver and equivalent to where I expect someone in the top 10 in the world to be. Master will now be set around the median of my group of solvers, which will be about where a 10th place USPC finisher will be or about top 100 in the world. In some sense these two times will inform on the mean and s.d. of the puzzle, and can highlight the Aha nature versus speed nature of particular solves as I have a few where one solver blazes through but the average solve takes much longer. Expert will be set at 2x the new Master time, which will often be close to the old 3x of GM but is hopefully more stable as it is using many more solvers’ data. There will no longer be a Novice time. It has not been a very useful measure at all, and I think has encouraged more disappointment than cheer from people trying to target it.

Next week will be “Think Outside the Box” week, with two puzzle styles where the clues are outside the grid. That should be a pretty easy Puzzle and Sudoku pair to identify, and I hope you enjoy the set of challenges I’ve lined up.

Best,
Dr. S.

Fourth in a series with puzzle solving tips. This time, basic steps to get through Cave puzzles.

While I’ve already written a good description of solving Cave (Corral) puzzles for the USPC, I’ve never drawn up some of the steps for more visual solvers. This week I hope to fix that by highlighting one of the more fundamental logic steps behind these puzzles.

(more…)

Still recovering from my trip to Boston so this week’s note will be brief. I hope you enjoyed the Arrow Sudoku and Cave Puzzles. This coming week will bring the first of the loop puzzle genres, Masyu, and Consecutive Sudoku, another of my favorite sudoku variants from the past, in this case from explorations in Mutant Sudoku.

As the topic for this week, I want to know what you think of the times given with the puzzle each day. For the competitive puzzlers, do you like seeing these times? Is the master time a bit too hard to reach? Would a slightly easier standard give a better target? For the recreational puzzlers, does seeing a time change how you approach the puzzle to care more about the clock than otherwise? Would you like an option to keep them hidden instead?

I am considering adding a self-reporting of times to the solve box once there is a finishers page for each puzzle. It is not a high priority at the moment as I view the times as a guideline to set an expectation for the puzzle, and not yet that my site is a “competitive puzzle site” like some others that record solving histories and such. But I welcome your input on any changes you might like me to think about going forward since I do have several excellent testers that have been giving me good data every day.

Cheers,
Dr. S

Third in a series with puzzle solving tips. This time, a dissection of Saturday’s Star Battle.

Jack Bross left an excellent set of starting tips for Star Battle in Dr. Sudoku Prescribes #14 so if you are struggling with these puzzles, start there. The hard Saturday puzzle required some unusual group recognition which I thought deserved to be highlighted.

(more…)

Today is probably the last day of the MIT Mystery Hunt and I’ll be puzzled out for the next few days, but I wanted to offer another Doctor’s Note on the state of Grandmaster Puzzles. After Jack Bross’s frightening guess of Thermo-Sudoku and Star Battle last week, I’m sure he can divine — when I say my favorite (non-Snyder) Sudoku variant, and my favorite “underrepresented” puzzle are coming this week — what you’ll see throughout the next six days.

After three weeks of puzzles, I wanted to hear your initial impressions on the puzzle difficulties here. Do you appreciate seeing a mix from “Monday” to the end of the week? Are some puzzles too trivial or too hard? Obviously some solvers will be in a very different part of their learning curves so I hardly expect to be able to satisfy everyone.

Finally, I wanted to thank Bram de Laat this week for helpful insight on the origins of Star Battle that have been added to that rules page. In addition to Bram, Wei-Hwa Huang and Nick Baxter have been particularly helpful in some of the research I’ve needed for puzzle origins and a thank you goes out to both of them as well.

— Dr. Sudoku

Second in a series with puzzle solving tips. This time, Nurikabe solving tips for last Friday’s puzzle.

A few simple Nurikabe rules will get you through most of the puzzles quite fast; but some of these rules are uncommon enough that you mainly learn them from solving rare puzzles like ours.

(more…)

Another week, and another set of puzzles I hope you really enjoyed.

By now you are probably sensing that during this “introduction” phase I will be showcasing one sudoku variation and one other puzzle style each week. This will continue this week with another of my own sudoku variations and another of my favorite puzzle styles. Can you guess which ones?

All of the sudoku variations are present in books I’ve published if you are interested in more; the puzzles — with the exception of TomTom Puzzles — are all styles that I’ve never had the opportunity to write for any domestic publisher. But now that I am publisher, all of these styles will be featured in “The Art of Puzzles” and I hope some of you choose to contribute puzzles to this book project.

This 50:50 split is good for the introduction phase of Grandmaster Puzzles, but does beg the question of what ratio of Sudoku to other puzzles you would like to see in the future. If the question was about most other sources of Sudoku, this would be an easy 0:100 for me. But Grandmaster Sudoku are very cool, and I hope any rating you give is reserved to the quality of Grandmaster puzzles in each of these genres, not your own preconceptions formed from “Number Place” puzzles that lack the elegance of hand-crafting.

In other site news, sometime this week I will add the much requested “pdf” form of each puzzle at the same time as posting for my paper solvers. Other changes will be coming by the end of the month, but certainly not this week as I prepare for a trip to Cambridge for the MIT Mystery Hunt. Better Luck This Time I always say!

— Dr. Sudoku

First in a series with puzzle solving tips. This time, TomTom solving tips for last week’s hard Thursday puzzle.

People always ask me how to solve puzzles and fast. My first answer is practice, practice, practice! My second is notation, notation, notation! After that, I say learn how to construct interesting puzzles and run through more involved logical deductions than most puzzles tend to have. In this column I intend to dissect some of our Grandmaster Puzzles with such interesting properties and at the same time reveal ways I look at puzzle styles that might help out in the future. This week’s topic is the Thursday TomTom, advertised at medium-hard difficulty, that few solvers beat in an expected time. While it shouldn’t need saying, SPOILERS AHEAD!

(more…)

I hope you enjoyed the first week of Grandmaster Puzzles. To some this may look just like a new home for my old blog. But this is actually the start to a large project I’ve dreamed of for awhile, to get more “puzzle” books published and improve the ecosystem for logic puzzle construction in the west where computer-generation is still the name of the day.

Eventually there will be a Sunday puzzle here. It will be bigger and better (but not necessarily harder) than any other puzzle during the week. But for the first many weeks, as I introduce some of the styles I’ll be publishing soon, Sunday will be the day for the Doctor’s Note. This will also be the right spot for you to comment in any way you want about the site such as new features you’d like to see (like a place to enter your time with your solution, or a page for leaderboard tracking). The site will continue to improve while the quality of the puzzle content stays as high as it can be. This will become the community for logic puzzle solving and I’d appreciate your likes, tweets, +1s, or other links to this page to help the community grow.

A big thank you goes out to Dave Millar, of Perplexible and The Griddle fame in the world of puzzles, for his help designing this website. Most of the images inside the frames are mine. But the rest is mostly him. He took some sketches from my puzzle notebooks and made a memorable blog theme. And he loaned some of his own API code to start our answer checking system which will get better as we go along.

So, what did you think of the first week of Grandmaster Puzzles? This week certainly had a very broad range in difficulty, but I expected both Sudoku and TomTom to be pretty familiar puzzles compared to what is coming. Next week will be a little more gentle, still with six quite interesting puzzles but two new styles.

–Dr. Sudoku