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Nikakoku

Updated on (created ) — Filed under: List Paper Ported Puzzle bay demi path pearl realm
Draw a line (along tile apothems) that separates the board in 2 regions, one for hollow and another for full circles.

Based on ruleset by Bay

First seen (2003) at Puzzle Communication Nikoli 102

This is an example puzzle - tap to interact!

Divide the board into exactly 2 regions, by drawing at most one line. No line may branch nor cross.

The line may not trace a cell edge.

The line must start and end on an edge of the board.

The line may not overlap a circle.

No region may contain circles of different colors.

Solved!
Rule panels by Random 8 on 28/09/2024

Bay composed the ruleset and first puzzles of Nikakoku (2003), shared at Puzzle Communication Nikoli, 102, alongside many other original paper puzzles.

In 2024 Pedro released the Nikakoku interactive app, leveraging the Kudamono Editor system. Pedro derived the programming logic, decided on colours & input modes and created all graphic assets, by tracing SVG paths. Rule panels by Random 8 on 28/09/2024.

All puzzles listed on this page have a single, unique solution. Brand-new puzzles are proudly submitted by their authors regularly, while historic puzzles gain a new life in the interactive Kudamono format: here transcribed for the first time, with permission from each author, on a unit-, genre- or general basis.

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This is part of a Masyu Doppel Pair.

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Start with a blank page (new Nikakoku puzzle).

Detailed editing instructions and shortcuts can be found at the manual.

The following variants are suggested: pearls-gray.

For more information about global variants, and how to combine multiple variants in a single puzzle, please see the variants page.

The following custom insertion shortcuts apply to Nikakoku:

Keyboard shortcuts for Nikakoku (S = solving, E = editing, S/E = both solving and editing )
Glyph When Submode Shortcut Description
www.w3.org/2000/svg'> SlineL → Iline (demi, solve): drag or click to draw definitive line (demi, solve)
www.w3.org/2000/svg'> EsymbolXAbsent tile: click or drag to place definitive symbol Absent tile
www.w3.org/2000/svg'> EsymbolBPearl black: click or drag to place definitive symbol Pearl black
www.w3.org/2000/svg'> EsymbolWPearl white: click or drag to place definitive symbol Pearl white
www.w3.org/2000/svg'> S/Eaux markOVertex o: click or drag to place auxiliary Vertex o
www.w3.org/2000/svg'> S/Eaux markQVertex q: click or drag to place auxiliary Vertex q
www.w3.org/2000/svg'> S/Eaux markXcross: click or drag to place auxiliary cross
www.w3.org/2000/svg'> S/Eaux lineS → Ksketch (demi): drag or click to sketch auxiliary line

Pressing an exclusive editing shortcut while solving, or vice-versa, causes a switch into that context. In contrast, shared shortcuts cause no switch, but are instead chosen to match the current context.

To copy the right url, simply follow the button sequence (export) → (link).

Likewise, a puzzle image may be exported via (export) → (picture).

Made a puzzle that you'd like to list here at Pedro's Works? Simply follow the Submission Guide!

When sharing a Nikakoku link on other social networks or across the fediverse please also include the hastag #KudamonoEditor in the post. Including the puzzle picture will usually enhance your post.

This table lists external sites and databases referencing Nikakoku.

Interlinks - other sites and databases listing this puzzle genre
Site Link Comment
PuzzleSquareJPNikakokuyou may also share your Nikakoku puzzles at PuzzleSquareJP: please include the hashtag #KudamonoEditor in the puzzle description

Please with any issues and suggestions.

There are specific instructions for live conflict highlighting and input issues, for improving the rule panels or reporting non-uniquenesses.

For any other bugs, please:

  • describe what you were trying to do,
  • what happened instead, and
  • send the current url (plus any visible error logs and possibly, supplementary screenshots).

You may check whether your bug is already covered by the unit tests (it may take a few seconds before the page loads fully). Any yellow boxes indicate a failed test. "Performance issues" currently indicate all passed tests, slow or not.

If you find a situation where the live conflict highlighter is not working as you'd expect (e.g. too aggressive, incorrect), please send a small test case url plus a brief explanation of what should be happening instead.

A good test case includes the smallest possible board, with the fewest possible elements, that is still able to unambiguously reproduce the issue.

For interface issues related input modes, or more generally to clicking/touching/dragging, keyboard shortcuts, etc… please submit an input test case, as detailed in the Inputs Initiative.

For simple typos/rewordings, a short email suffices. For more substantial changes, please refer to the rule panels guidelines.

If you find a non-uniqueness in one of the puzzles, please first check whether you are able to contact the puzzle author directly to request a fix.

If that seems impractical, please submit either:

  • a corrected, unique puzzle url (with solution), if you are able to suggest a fix (preferred); or
  • a puzzle url solved up to the point where the puzzle stops being unique; or
  • multiple urls (one per solution)
2024-07-23 Thanks to Chifur for sending the metadata for Nikakoku ニカコク! 2024-09-26 Thanks to PinkHoodie for sending 4 rollour classics, in anticipation of the release, and making a Masyu Doppel Pair! 2024-09-29 Random 8 successfully navigated the intrincacies of the genre to make the rule panels for Nikakoku ニカコク. In this genre, the interdependent constraints (no-branching and divide in two regions) make it logically impossible to display a single error per panel — so the first error panel displays those errors all at once. 2024-09-29 Nikakoku highlighting upgraded to reduce interference with variants (PinkHoodie) 2024-09-29 PinkHoodie sent a turning,straight puzzle for rollout. Thank you! 2024-10-03 Local variant pearls-gray added to Nikakoku ニカコク, a suggestion by justkirb. Later on it may be upgraded to a global-variant. A puzzle by PinkHoodie was updated to use this variant. 2024-10-04 Recent regression detected by Random 8 was fixed (cause: trying to set non-existing cursor name; cursor name should be set even in the absence of automode)