I wrote this puzzle for the final play-off round of this year's World Puzzle Championship, and the world's best puzzle solvers all found it hard. So congratulations to anyone who manages it without help!
Gareth
Posted 21st Sep 2014 at 00:39
elfinmyst Rated puzzle: HardCompletion time: 14:37Used 'show wrong moves' Used 'check puzzle' when incorrect
Glad to hear that, I found it difficult and needed help :)
Posted 21st Sep 2014 at 03:31
GotLag Rated puzzle: EasyCompletion time: 3:43
Is it expected in this kind of puzzle that after some initial deductive work, you'll then need to just start making guesses and seeing what fits? It doesn't take too long but I wonder if I'm missing something.
You can complete most of the puzzle without any experimentation, and essentially it becomes a packing problem for the 17 and 10 regions, plus one of the middle 3 regions will also be unresolved. Basically you need to look and see how the 17 and 10 could both be simultaneously fulfilled (plus the middle 3). Many World Puzzle Championship-level Nurikabe are designed in this way, whereby the challenge is to find a way to fit all the regions in together - but you don't need to arbitrarily guess, which I would describe as a point in a puzzle where you have to pick an option and continue and hope for the best. In this case when you pick an option you already know you need to make the regions fit together and so you can find out immediately if they don't work in the way you'd hoped.
Nurikabe is the kind of puzzle where optimising parts of the grid by eye can be part of the challenge; of course you can't always do this in other types, like Sudoku, where you would quite literally be guessing if you couldn't see the next discrete deduction.
So to answer your question, it depends on where you got to - if you had just the 17 and 10 left, plus the middle 3, then you had got as far as you could without needing to start working out how to pack everything in. If you stopped earlier on, you probably missed something.
Gareth
Posted 22nd Sep 2014 at 21:48
pevrill Rated puzzle: EasyBest completion time: 3:51Time on first attempt: 6:04
Feeling even more chuffed to still have fastest unaided a day later! I did essentially what you're describing, Gareth, by sorting most of the puzzle except the 2 biggies, and then doing a bit of "what-if" - most difficult bit was keeping all the black connected.
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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'.
Gareth
You can complete most of the puzzle without any experimentation, and essentially it becomes a packing problem for the 17 and 10 regions, plus one of the middle 3 regions will also be unresolved. Basically you need to look and see how the 17 and 10 could both be simultaneously fulfilled (plus the middle 3). Many World Puzzle Championship-level Nurikabe are designed in this way, whereby the challenge is to find a way to fit all the regions in together - but you don't need to arbitrarily guess, which I would describe as a point in a puzzle where you have to pick an option and continue and hope for the best. In this case when you pick an option you already know you need to make the regions fit together and so you can find out immediately if they don't work in the way you'd hoped.
Nurikabe is the kind of puzzle where optimising parts of the grid by eye can be part of the challenge; of course you can't always do this in other types, like Sudoku, where you would quite literally be guessing if you couldn't see the next discrete deduction.
So to answer your question, it depends on where you got to - if you had just the 17 and 10 left, plus the middle 3, then you had got as far as you could without needing to start working out how to pack everything in. If you stopped earlier on, you probably missed something.
Gareth
You can however view other players' statistics and comments in the tables above.