Techniques spanning more than one grid in overlapping puzzle

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Techniques spanning more than one grid in overlapping puzzle

Postby tarek » Tue Jul 29, 2008 6:17 am

This issue has been brought forward recently & is quite interesting.

As I am finalising my overlappping puuzle solver, a programmers perspective has also surfaced.

An overlapping puzzle such as the "Samurai" variant can be viewed as 5 overlapping puzzles or as 1 big puzzle.

If you see it as 5 overlapping puzzles then you would then see that twhat happens in the overlapping section in 1 grid has to be carried to that section in the other grid (or grids)

If you look at it as 1 big puzzle, then the overlappingsections are only special cells that can SEE more cells.

This will have an impact on our solving tecniques.

My interest would be mainly in FISH & to see if some fruitful cover sectors can be used from more than one grid.

Examples here would shed a light on this matter

No need to limit things to FISH only.

I will post an example as soon as I come across one.

tarek
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Postby Glyn » Tue Jul 29, 2008 9:36 am

tarek Perhaps the most suitable Gattai to start fishing in for an early catch would be DoubleDoku, Gattai-3, Butterfly, Flower and Kazagurama (Windmill) as these have a high proportion of overlap cells. In some cases a cell can be a member of 3 or even 4 grids. This might help check out any code.
The narrowness of intersection zones of in the more popular Samurai and Clueless (9 cells only) may restrict the types of fish permissible.
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Postby Jean-Christophe » Tue Jul 29, 2008 7:18 pm

In my soft JSudoku, I opted for "1 big puzzle" since this was a natural extension to the variants I already supproted.

Here is a samurai which requires patterns spanning several sub-grids. JSudoku used some XY-chains and ALS-XZ.

Code: Select all
..1..6.4.......98.7.6..2.......8...1...4..8.52.3.......1..4....42..........27....
..9....8.....7.2.95.1.3....9.....4.8..5..9......3.4..6......86....7.2..........7.
...3.8...............9.7...2.1............1249.6..........3........2........5....
..93..............6.7.5.........1.5..12..........46.3..7.9..5..8.....9.7.2.7.4...
...8..........1.9....7...622.4..7.........329.9.5....7....7...1.29.5......5.639..
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Postby Pat » Wed Jul 30, 2008 6:11 am

hey tarek,

the following frog
is probably not what you had in mind--

Code: Select all
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-------+-------+------
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-------+-------+-------
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 / / / | . . . | . . . | * * *
 . . . | . . . | . . . | . . .
        -------+-------+------
         . . . | . . . | . . .
         . . . | . . . | . . .
         . . . | . . . | . . .
        -------+-------+------
         . . . | . . . | . . .
         . . . | . . . | . . .
         . . . | . . . | . . .

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Postby tarek » Wed Jul 30, 2008 1:33 pm

Pat wrote:hey tarek,

the following frog
is probably not what you had in mind--
I was thinking of something like this:
Code: Select all
 . . . | . * . | . . .
 . . . | . * . | . . .
 . . . | . * . | . . .
-------+-------+------
 . . . | . * . | . . .
 . . . | . * . | . . .
 . . . | . * . | . . .
-------+-------+-------
 . . . | . X . | X / X | / / / | / / /
 . . . | . / . | * * * | . . . | . . .
 / / / | / X / | X / X | . . . | . . .
                -------+-------+------
                 . . . | . . . | . . .
                 . . . | . . . | . . .
                 . . . | . . . | . . .
                -------+-------+------
                 . . . | . . . | . . .
                 . . . | . . . | . . .
                 . . . | . . . | . . .
g1r9g2r1/g1b9g1c5 ==> [g1r123456c5][g1r8c789]<>X


(For he example, ignore the g2r1/g2b1 intersetion)

The frog you've posted has a LOL relationship where *** should be the same as ///.

It is easier to demonstrate it with a bigger fish

tarek
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Postby Jean-Christophe » Wed Jul 30, 2008 4:04 pm

tarek wrote:I was thinking of something like this:
Code: Select all
 . . . | . * . | . . .
 . . . | . * . | . . .
 . . . | . * . | . . .
-------+-------+------
 . . . | . * . | . . .
 . . . | . * . | . . .
 . . . | . * . | . . .
-------+-------+-------
 . . . | . X . | X / X | / / / | / / /
 . . . | . / . | * * * | . . . | . . .
 / / / | / X / | X / X | . . . | . . .
                -------+-------+------
                 . . . | . . . | . . .
                 . . . | . . . | . . .
                 . . . | . . . | . . .
                -------+-------+------
                 . . . | . . . | . . .
                 . . . | . . . | . . .
                 . . . | . . . | . . .
g1r9g2r1/g1b9g1c5 ==> [g1r123456c5][g1r8c789]<>X


No need of any fish here. Simple intersection gives:
Code: Select all
X for g2r1 locked @ g2r1c13 -> locked for g2b1, g1r7 -> g1r9c5 = X (HS)


tarek wrote:The frog you've posted has a LOL relationship where *** should be the same as ///.

Yes, it's called Twin nonets
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Postby tarek » Thu Jul 31, 2008 6:06 am

Jean-Christophe wrote:No need of any fish here. Simple intersection gives:[code]X for g2r1 locked @ g2r1c13 -> locked for g2b1, g1r7 -> g1r9c5 = X (HS
You obviously missed that I asked you to ignore this fact for the purpose of demonstration the x-wing in the lines that followed the diagram.

The fact is, we need a better example:D

The ALS are great & will force you to look at the puzzle as 1 entity.

BTW, intersections are 1-fish & should follow the same logic, a bit more difficult though for them to span different grids & remain fruitful.

tarek
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Postby Pat » Fri Aug 01, 2008 7:07 am

Jean-Christophe, thanks for providing the SuDoPedia reference

tarek, the twin nonets -- my un-exciting frog -- is the closest i could come to anything which might resemble fish. what i'm trying to say is, i really have no expectation of finding any fruitful new type of fish here. ( i say nothing about ALS or any other methods. )
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Postby tarek » Fri Aug 01, 2008 8:25 am

Pat wrote:what i'm trying to say is, i really have no expectation of finding any fruitful new type of fish here. ( i say nothing about ALS or any other methods. )
I also harbour no such expectations. The exciting thing to me was to find mutant fish with (base/cover) sectors coming form different grids.

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