Nurikabe by Tom Collyer
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Theme: Increasing Ripples (Originally for the 2015 Polish Puzzle Championship Online Qualifier)
Author/Opus: This is the 27th puzzle from our contributing puzzlemaster Tom Collyer.
Rules: Standard Nurikabe rules.
Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.
Time Standards (highlight to view): Grandmaster = 2:00, Master = 2:30, Expert = 5:00
Solution: PDF
Note: Follow this link for other classic Nurikabe. If you are new to this puzzle type, here are our easiest Nurikabes to get started on.
Just before working on this one I had been looking at a Fillomino. So I confused myself for some time trying to get started on this one because I kept imagining islands connecting like numbers. Once I reminded myself that the rules require exactly one given per island things progressed much more nicely.
I’ve done grids that function as both nurikabe/numberlink and cave/fillomino before, but I’m not sure that nurikabe/fillomino would quite work 🙂
It’s pretty easy to show that a Nurikabe/Fillomino can work at a trivial size, (think, a 2×2 grid with a single given “1”).
But having an interesting puzzle at a larger size would definitely be tough to pull off. You need as many cells in hidden Fillomino polyominoes as you have cells of the Nurikabe wall. And it’s going to be tough to clue that many hidden polyominoes uniquely with only one available clue per Fillomino polyomino.
I’ve seen you use this opening with the 4 in the corner at least twice before (#99 and #128 on your blog). It was a bit of a deja-vu.
Well – it’s just an opening – most novelty in nurikabe needs a bit of development in the solution of the puzzle first. I used to have quite a thing for starting with an X pentomino as well. Both are far less common than opening a nurikabe with pairs of diagonally adjacent givens.
neat puzzle.5:58