UK Puzzle Association

Yes I agree this is what we should do, and I think this is what Tom will do. If I understand, he wanted to start with discussions concerning examples to have a better idea when it comes to speaking about properties (not sure if it will succeed). But yes, normally it should be the opposite way: to d...

My thoughts so far: (a) Which variation is considered a valid sudoku variation? I don't think this question makes sense as stated in terms of something being valid or not. I'll try and expand upon this a little more however in terms of what I've heard so far. I have a lot of time for Thomas's sugges...

I've unlocked this post as I continue to edit and rearrange this - however categorising each of the examples is not an exact science and if anyone has another opinion about how to classify these examples then I'd be very happy to hear.

This is interesting. I've had in mind (somewhat provocatively) to post a Killer Sudoku example in this forum, as I don't think from one point of view there is too much difference between the two...

Hi Fred - could you post a link to the source of this puzzle please?

I thought that Eight Winds and Wranglers were kind of strange types to have on a round called Classics and Evergreens, but reading more about the competition the format guarantees there will be two lots of two "exploratory" variants on each and every round. And I don't think anything more needs to b...

Hi Berni, thanks very much for your thoughts. The main issue I have with the description of trial and error as a logical technique is the observation that, if you are fortunate from a speed solving point of view, you get lucky and don’t hit an error. Although I am not 100% certain, I can’t imagine t...

The 2019 season starts off this weekend, with Dutch authors taking their traditional 1st round spot.

http://gp.worldpuzzle.org

This thread is a work in progress, but aims to provide a catalogue for each of the examples in this forum grouped very roughly into themes. This should hopefully be a bit more convenient for people wishing to navigate the forum. (Lack of) (Clear) Regional Constraints - Disjoint Regions Sudoku - Free...

Tetris Sudoku [WSC 2011].png This puzzle shares some similarity with Star Battle Sudoku, in that the puzzle requires you to place some (repeated) symbols with additional properties - in this case the additional symbols are shaded squares, and the additional constraint is that these must all be conn...

[Placeholder as the attachment size is apparently too large - I'll try and fix later] For those who can still remember it, this puzzle required the placement of symbols - in the form of pictures of famous Budapest landmarks - and there were clues in the grid that had to be moved by exactly one cell ...

Wrong Puzzles [WSC 2011].png The first round of the 2011 WSC featured a booklet of examples similar to the above, where the only thing required of the solver was to mark whether the solution grid was a valid Sudoku solution, or not. This does not require the solver to place any numbers. This year w...

Thanks - that one gets a slightly higher diabolical rating of 559 at http://www.sudokuwiki.org/sudoku.htm

It depends exactly what we mean by solve. Many solvers only consider something to have been solved "logically" if at each stage of solving the puzzle, the solver is 100% confident that the number placed is part of the solution. Nevertheless, from a competition point of view, the only thing that matt...

Apologies for the multi-dimensional nature of the poll. I hope to have given a good representation to different views on this one, but when we are talking about several examples all at once it becomes hard to specifically tailor the poll to cover all bases. If you happen to feel differently to any o...

Thomas posted a lot of background information on his Grandmaster puzzles-blog, but since I'm not 100% sure, if giving the reference is enough to meet copyright restrictions, I chose a different picture as example. Richard will not sue me for sure :D https://www.gmpuzzles.com/blog/sudoku-rules-and-i...

No need to be sorry, it’s a time consuming task and I’m more than glad if people can help me out thanks for posting!

I would say the special series is just a case of really bad phrasing - I don’t think there is anything there to upset anyone who isn’t also upset by consecutive sudoku. I would say the thing to focus on is the two solutions. On the other hand, it would be interesting if there was some opinions again...

This is a very interesting case where I’m not sure if I have a definite personal opinion about! For classic sudoku, the requirement is that 1-9 appear everywhere exactly once. This is equivalently described as appears everywhere “at most once” - ie non repeating - or “at least once” - a less common ...

This also featured in the 2011 WSC, but you beat me to it.

In theory this puzzle requires the drawing of regions as well as the placement of numbers

I don't see myself how (1) "What is a Sudoku?" is a question I have anything more to say about than the basic thoughts above. An Arrow Sudoku is not a sudoku. A Diagonal sudoku is not a sudoku. It has some cells with more than 3 unique placement constraints. They are at best Sudoku Variations. Ther...

I have to say I'm struggling to see any interpretation where I can see this being a Sudoku - does anyone feel any differently, and if so, why? This is not to say that non-examples (if indeed this is a non example) are not useful in their own right. It is certainly very useful to have non examples to...

I feel this productive discussion is beginning to bear fruit - thank you! The example of adding a pair of diagonal constraints reminds me of some of some examples responsible for the bad feelings expressed following the 2009 WSC - perhaps this discussion is better placed in this thread: http://forum...

Zilina Sudoku [WSC 2009].png This (in)famous example was used in the final play-off to determine the World Sudoku Champion in 2009. The grid features two sorts of "extra regions" - firstly the coloured letter shapes, where numbers placed are not permitted to repeat, and secondly the marked diagonal...

And what exactly is a big step? Consider that: - 50m freestyle and 100m sprint are both races in which fields of competitors look to get to one end of the course as fast as possible in order to finish in 1st place. - 50m freestyle is swimming in water, and 100m sprint is running on a track. In one s...