WC2018 Kazaguruma Special

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WC2018 Kazaguruma Special

Postby 1to9only » Tue Jun 12, 2018 5:00 am

Just in time for the World Cup:

WC2018 Kazaguruma Special - [EASY - singles only]
Code: Select all
4...3...92....576.6...7925..3.58...2.76......9...6.47.7.........4.......369......
1.49..57332..71...7...6.........3......7.89.6......72....4..16....2..84......9..7
.................................................................................
9..6......24..9....18..4....96......4.23.5......4.........4...8...76..53269..37.4
......431.......6.........5.35.1...7......59.9...83.4..4685...2.926....45...7...9
Attachments
WC2018 Kazaguruma Special (108.Easy).pdf
kazaguruma - empty middle grid
(40.49 KiB) Downloaded 20 times
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Re: WC2018 Kazaguruma Special

Postby 1to9only » Tue Jun 12, 2018 5:15 am

These kazagurumas (windmills) are difficult to find, the first one suddenly popped out after I was messing about with my gattai-maker, and had been tweaking it for these puzzles and maybe running it for the 20th or 30th time(!), long after I would normally have given up... I ran the maker in a batch file to produce 100 kazagurumas, several times, and the chances of generating a puzzle with an empty middle grid is about 1 in 100 attempts!!!
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Re: WC2018 Kazaguruma Special

Postby Hajime » Tue Jun 12, 2018 11:35 am

1to9only wrote:These kazagurumas (windmills) are difficult to find ... chances of generating a puzzle with an empty middle grid is about 1 in 100 attempts!!!

I agree, also my generator/solver has the same problem.
Interesting.... what can I/we do about that :roll:
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Re: WC2018 Kazaguruma Special

Postby 1to9only » Tue Jun 12, 2018 2:12 pm

I guess I got a lucky hit! I lost count of tweaks made, tried one a few times, it didn't work, tried something else, etc... Here are some of the things tried (in no particular order!), towards getting a puzzle with an empty middle grid:

1) Enable naked and hidden singles only (easy puzzles), the added bonus: the program runs quicker(!). I've tried creating more difficult puzzles (i.e. enabling locked candidates and naked/hidden pairs for medium puzzles) - this is 3 times slower!! - and I think the success rate is lower as well!!

2) Generate a 'normal' kazaguruma (windmill), with (eight) empty overlapping boxes (nonets) - the majority of times, the puzzle is unsolvable (lots of unique rectangles left over) - occasionally (the 1-in-100 attempts) a puzzle with an empty middle grid is made. I've tried emptying the whole middle grid, the success rate I've had with this method is: zero.

3) Other times, the middle box in the middle grid will have givens - remove them! - re-solve - [most times, the puzzle becomes unsolvable!] sometimes, I've ended up with a puzzle with an empty middle grid!! This works better with the easy puzzles mode, much less well with the medium puzzles mode. With the easy puzzles, removing the givens in the middle box of the middle grid has sometimes resulted in a medium puzzle!!

The highlighted items seem to work for me.
Last edited by 1to9only on Tue Jun 12, 2018 5:08 pm, edited 1 time in total.
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Re: WC2018 Kazaguruma Special

Postby enxio27 » Tue Jun 12, 2018 4:56 pm

:D :D :D
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Re: WC2018 Kazaguruma Special

Postby tarek » Tue Jun 12, 2018 5:15 pm

Tip:

Process a large number of solution grids to remove central clues
Call these special grids “puzzles”
Solve “puzzles”
Filter only valid “puzzles”
Rename valid “puzzles” into “Kazaguruma WC special solution grids”

Happy hunting!!!

Tarek
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Re: WC2018 Kazaguruma Special

Postby tarek » Tue Jun 12, 2018 5:16 pm

tarek wrote:Tip:

Process a large number of solution grids to remove central clues
Call these special grids “puzzles”
Solve “puzzles”
Filter only valid “puzzles”
Rename valid “puzzles” into “Kazaguruma WC special solution grids”

Happy hunting!!!

Tarek


P.S whoops, I just gave you a tip on how to do the same with other types of gattai
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Re: WC2018 Kazaguruma Special

Postby enxio27 » Tue Jun 12, 2018 7:44 pm

tarek wrote:P.S whoops, I just gave you a tip on how to do the same with other types of gattai


:lol:
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Re: WC2018 Kazaguruma Special

Postby Hajime » Thu Jun 14, 2018 1:24 pm

Did not follow the instructions of tarek. Don't have that much time :)
@1to9only:
First generate a vanilla windmill.
Kick out the middle grid, nr 3.
Solve the puzzle.... unsolvable (lots of unique rectangles left over in nr 3)
Shuffle manually some rectangle digits of nr 3 up (in 1 and 2) and down (in 4 and 5).
And here is the symmetric result.
@enxio27:
I added the pencilmarks.

The puzzle has 233 cells to fill, moderate (box-lines and naked/hidden sets).

image
Hidden Text: Show
[img]
VanillaWindmill950.png
VanillaWindmill950.png (241.49 KiB) Viewed 212 times

[/img]

code
Code: Select all
690000000501040600043608001005012930010400052002800700080000000000000000007000000
000000043002040809900802650000750900000006080000001500000407090000065000000090400
000000000000000000000000000000000000000000000000000000000000000000000000000000000
009040000000810000020607000001400000030700000002081000016905004207060100340000000
000000600000000000000000040008009200150006090032810700600405320004020106000000078
Last edited by Hajime on Sat Jun 16, 2018 7:25 am, edited 2 times in total.
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Re: WC2018 Kazaguruma Special

Postby tarek » Fri Jun 15, 2018 5:42 pm

With the limited hardware resources 10 years ago compared to today. I used my method to create a database of special solution grids to use as source for these special puzzles. You can generate a special puzzle every time. It will actually save time if you are planning to post more of these puzzles. (64 games ----> 64 puzzles)

Also the ability to morph puzzles is a quick cheat that helps when resources are limited.

Every puzzle maker has their own touch & way to reach the desired result. I like my puzzles to have a degree of minimality (least redundancies) and symmetric.

Well done for dedicating time to creating these "Gattai makers". It must be pleasing when you have the power to create and solve virtually anything!!!

The next level in your puzzle making is going to be RATING the puzzles which will be more time consuming in the Gattai setting!!!
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Re: WC2018 Kazaguruma Special

Postby Hajime » Sun Jun 17, 2018 5:25 pm

tarek wrote:Well done for dedicating time to creating these "Gattai makers". It must be pleasing when you have the power to create and solve virtually anything!!!

A week ago I thought it is impossible to solve a vanille empty center grid in a windmill. Now I made one. It is indeed a rollercoaster. About half a year ago terms like "clueless" an "nonet" were unknown to me.
Soon I will publish my Solver and Generator (in Excel), after it is proven OK by beta tester. Wait for the results.
Also I am now creating a puzzle with my name in it.
PS: In 2008 I made an Excel to show the candidates of a normal Sudoku. Had a pauze, and 10 years later I started to solve and generate overlapping variants. Now I am addicted.
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Re: WC2018 Kazaguruma Special

Postby enxio27 » Fri Jun 22, 2018 9:27 pm

tarek wrote:Tip:

Process a large number of solution grids to remove central clues
Call these special grids “puzzles”
Solve “puzzles”
Filter only valid “puzzles”
Rename valid “puzzles” into “Kazaguruma WC special solution grids”


tarek, please check your private messages.
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Re: WC2018 Kazaguruma Special

Postby tarek » Sat Jun 23, 2018 12:30 pm

enxio27 wrote:tarek, please check your private messages.
i did :D
I get notified by email when a PM is sent to me!!!
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