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Comments and Results for 'Nurikabe 242'

StateTypeTitleSizePlayedAvg timeRating (#users)YoursYour bestPublishedExpires
UnplayedNurikabeNurikabe 24210x101018:19Mild (50)Subscribers only30th Jan-
Show full chart rankings for Nurikabe 242
Your puzzle statistics First solution time distribution Overall puzzle statistics
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Slowest 10% not shown
0:00
19:55

Solution time without 'show wrong'
Slowest 10% not shown
0:00
26:41

Unaided first solution time
Slowest 10% not shown
0:00
13:10
Completed by73 users
Best time without any aid2:36 by TashaPuss
Best time with minor aid2:17 by Anonymous
Best time with major aid1:35 by oseyerus13
Best time with show wrong
or multiple sessions
0:40 by Cate-Lyn
Average solve time with no or minor aid5:52
Average solve time with no aid5:59
Average difficulty rating - all players3.7/10.0
Average difficulty rating - no aid2.5/10.0
Average difficulty rating - minor aid4.4/10.0
Average difficulty rating - major aid4.4/10.0
Average difficulty rating - show wrong or
multiple sessions
4.5/10.0
9 comments (Add new comment)
Posted 12th Feb 2021 at 06:52
JoergWausW Daily subscriber Best completion time: 3:10 Time on first attempt: 4:51 Used 'show wrong moves' Used 'check puzzle' when incorrect
This one seems to be the last one for now. We had a new one about every three/four days.
In the last 13 months there were exactly 120 Nurikabe puzzles.

Either the random engine is playing a good one (pausing three times as long as average after exactly 10 dozens) or we need more... please???

Posted 16th Feb 2021 at 03:06
gareth Administrator Daily subscriber Rated puzzle: Moderate Completion time: 2:17 Used 'check puzzle' when incorrect
No, you were right. I've just added 10 more to the queue.
Posted 16th Feb 2021 at 03:06
gareth Administrator Daily subscriber Rated puzzle: Moderate Completion time: 2:17 Used 'check puzzle' when incorrect
The next one will be on the 19th February.
Posted 16th Feb 2021 at 03:18
gareth Administrator Daily subscriber Rated puzzle: Moderate Completion time: 2:17 Used 'check puzzle' when incorrect
By the way if anyone reading this fancies writing some Nurikabe puzzles, let me know. :)
Posted 16th Feb 2021 at 20:10
Thoult Has started but not yet finished this puzzle
I'd genuinely be interested if you have any pointers.

I've often assumed you have an internal style guide for many of your puzzles, especially Nurikabe!

Posted 16th Feb 2021 at 21:25
Last edited by gareth 16th Feb 2021 at 21:39
gareth Administrator Daily subscriber Rated puzzle: Moderate Completion time: 2:17 Used 'check puzzle' when incorrect
I don't have a style guide because I've always written all the puzzles myself. :) I usually try to make them symmetrical, but Nikoli (who invented the puzzle) don't bother so it's really not a requirement.

Other than that, the one style rule I have is that if you pretend that there isn't a rule that every island has to have a number on it, the solution would still be unique - i.e. it wouldn't be possible to add any extra empty islands anywhere in the grid and still have the solution be otherwise valid. (Imagine a 4x4 grid with a 2x2 island in the middle - you could then add an extra 1x1 island to any of the four corners while still keeping all the shaded areas connected. Even if it was a valid nurikabe under the usual rules, I wouldn't consider that a good puzzle because that uniqueness would come only because of the must-have-a-number rule. That said, there are a small number of puzzles I've published that break that rule!). I have this 'rule' because Nikoli also have it, and more broadly it tends to make the puzzles more interesting by making the must-be-shaded constraint stronger. It can be broken if it must be, but it's generally a good guide to what is and what isn't a good puzzle - having lots of those unneeded shaded squares generally means the puzzle is less interesting.

I usually create 10x10 puzzles because you don't have to worry too much about the difficulty - even a really hard nurikabe puzzle is tractable at 10x10 - but they could be any size. All I need is a picture of a grid and I can type it into my software which will check it is unique, then generate the data content to upload to the puzzlemix server. A spreadsheet or other file format is fine too. Oh, and currently puzzlemix doesn't support areas larger than 35 squares. But the grid itself can be any size, and doesn't have to be square.

Currently puzzlemix can't credit puzzle authors, although it might in the future when I expand it as I'm planning to. I can offer free subscriptions and free puzzle sets in return, or access to brainedup.com or content on sudokuxtra.com, but if anyone started consistently making usable puzzles at some point then I could also offer payment - although I should say that Nurikabe is one of the few types I need help with, since most other types I have plentiful supplies of already.

And obviously the two other main constraints are that any puzzle should be unique, and not copied from somewhere else. :)

If you wanted to test the waters, you could make a single 8x8 or 10x10 puzzle and email it to me at gareth@puzzlemix.com?

Posted 17th Feb 2021 at 20:01
JoergWausW Daily subscriber Best completion time: 3:10 Time on first attempt: 4:51 Used 'show wrong moves' Used 'check puzzle' when incorrect
My two shaded cells:

1)

- if symmetry is needed you could drop other clues - but that would chance the rules.
- if symmetry is the outcome on default: The puzzle might be way easier.

I guess - like Slitherlink or Hitori or Hanjie - symmetry should not be a factor creating a puzzle.

2)

islands without numbers? I don't get the concept yet. Unless there was a rule to fill as much white as possible, maybe?

Then your empty 4x4 grid with just a white 1 in one corner would have a unique solution.


Another possible setup: you put a white 1 at (1/1) and a white blank at (2/2) in a still 4x4 grid - that also would be uniquely solvable (but only if there are no other islands allowed). Is this what is meant?

Maybe I should read the rules again....

Posted 17th Feb 2021 at 20:52
gareth Administrator Daily subscriber Rated puzzle: Moderate Completion time: 2:17 Used 'check puzzle' when incorrect
Hi JoergWausW,

I was only talking about design guidelines - nothing to do with the rules of the actual puzzle itself.

I can't think of any puzzle which requires symmetric givens - but they tend to look nicer when they have them. On the shading, it's very easy to make a puzzle which is technically fine but which isn't very interesting to solve, which is what I was talking about avoiding.


Gareth

Posted 18th Feb 2021 at 06:00
JoergWausW Daily subscriber Best completion time: 3:10 Time on first attempt: 4:51 Used 'show wrong moves' Used 'check puzzle' when incorrect
I see.

Design of looks vs. design of possible solution mechanism.

Understood (I hope).

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Key

  • A yellow/light blue highlight in the time distribution charts highlights your time, where relevant.
  • Rating scores out of 10.0 show the average difficulty rating chosen by users, where 1.0 is "Easy" and 10.0 is "Hard".
  • If a puzzle is opened more than once, including by loading from a saved position, then this is potentially a significant aid so it is listed as being completed with 'multiple sessions' for the purpose of the best time/average rating displays above.
  • Minor aid is defined as no more than one use of 'Check solution' when incomplete and/or no more than one use of 'Check solution' when wrong; and/or using highlighting aids (show repeated digits, show broken inequalities and show valid/invalid placements [slitherlink] only). Major aid is any and all other use of the solving aids except for 'show wrong'.

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