ED=1.9/1.9/1.9 SixySudoku puzzle

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ED=1.9/1.9/1.9 SixySudoku puzzle

Postby 1to9only » Sun Dec 08, 2019 12:06 pm

This puzzle uses the same SixySudoku constraints from post#1 here:

Code: Select all
+-----------+-----------+
| .   .   1 | 2   .   . |
+---+   +---+---+   +---+
| . | 3 | .   4 | . | . |
|   |   |       |   |   |
| . | . | 5   . | . | . |
|   |   |       |   |   |
| . | . | .   . | . | . |
|   +---+-------+---+   |
| .   . | .   . | .   . |
|   +---+       +---+   |
| . | .   .   .   . | . |
+---+---------------+---+

Code: Select all
+----------------------------+--------------------------+
|  456       456      1      | 2        356      356    |
+---------+         +--------+--------+        +--------+
|  256    |  3      | 26       4      | 156    | 156    |
|         |         |                 |        |        |
| *12346  |  246    | 5        136    | 1346   | 12346  |
|         |         |                 |        |        |
| *12346  |  246    | 236      136    | 13456  | 123456 |
|         +---------+-----------------+--------+        |
| *123456   -12456  | 2346     1356   | 123456   123456 |
|         +---------+                 +--------+        |
| *123456 | =12456    2346     1356     123456 | 123456 |
+---------+------------------------------------+--------+

Code: Select all
..12...3.4....5..................... SIXY ED=1.9/1.9/1.9
..12...3.4....5................1.... 1.9, Direct Claiming: Cells R3C1,R4C1,R5C1,R6C1: 1 of column in cage

r6c2=r1c3 always, and r6c5=r1c4 as well.
.
1to9only
 
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Joined: 04 April 2018

Re: ED=1.9/1.9/1.9 SixySudoku puzzle

Postby urhegyi » Thu Feb 04, 2021 11:46 pm

Here are two more of them with the same pattern : difficulty 5 stars from the free Peter Ritmeester e-book:
Sudoku_Sixy_Wacky_free_E-pagina's-16-1.png
Sudoku_Sixy_Wacky_free_E-pagina's-16-1.png (68.65 KiB) Viewed 263 times

I understand now the LOL(law of leftovers technique) which makes it a lot easier.
Solution of the first one:
Hidden Text: Show
Code: Select all
251463
364152
542316
136524
425631
613245

Solution of the second one:
Hidden Text: Show
Code: Select all
165432
234561
641253
523614
416325
352146
Last edited by urhegyi on Fri Feb 05, 2021 1:00 pm, edited 3 times in total.
urhegyi
 
Posts: 539
Joined: 13 April 2020

Re: ED=1.9/1.9/1.9 SixySudoku puzzle

Postby urhegyi » Thu Feb 04, 2021 11:57 pm

Thisone from a post of Hajime came to my attention today:
Image
Same rules as 6x6 jigsaw and 2X3 blocks.
I was able to solve it without the knowledge of the two extra constraints.
solution:
Hidden Text: Show
Code: Select all
625143
431526
542361
316452
164235
253614
urhegyi
 
Posts: 539
Joined: 13 April 2020

Re: ED=1.9/1.9/1.9 SixySudoku puzzle

Postby urhegyi » Fri Feb 05, 2021 2:34 pm

1to9only wrote:This puzzle uses the same SixySudoku constraints from post#1 here:

Code: Select all
+-----------+-----------+
| .   .   1 | 2   .   . |
+---+   +---+---+   +---+
| . | 3 | .   4 | . | . |
|   |   |       |   |   |
| . | . | 5   . | . | . |
|   |   |       |   |   |
| . | . | .   . | . | . |
|   +---+-------+---+   |
| .   . | .   . | .   . |
|   +---+       +---+   |
| . | .   .   .   . | . |
+---+---------------+---+

Code: Select all
+----------------------------+--------------------------+
|  456       456      1      | 2        356      356    |
+---------+         +--------+--------+        +--------+
|  256    |  3      | 26       4      | 156    | 156    |
|         |         |                 |        |        |
| *12346  |  246    | 5        136    | 1346   | 12346  |
|         |         |                 |        |        |
| *12346  |  246    | 236      136    | 13456  | 123456 |
|         +---------+-----------------+--------+        |
| *123456   -12456  | 2346     1356   | 123456   123456 |
|         +---------+                 +--------+        |
| *123456 | =12456    2346     1356     123456 | 123456 |
+---------+------------------------------------+--------+

Code: Select all
..12...3.4....5..................... SIXY ED=1.9/1.9/1.9
..12...3.4....5................1.... 1.9, Direct Claiming: Cells R3C1,R4C1,R5C1,R6C1: 1 of column in cage

r6c2=r1c3 always, and r6c5=r1c4 as well.
.

solution:
Hidden Text: Show
Code: Select all
541236
632415
125643
463152
254361
316524
urhegyi
 
Posts: 539
Joined: 13 April 2020

6x6 Jigsaw Blocks (JSBs)

Postby 1to9only » Fri Feb 05, 2021 3:30 pm

It's been over a year since I looked at these sixy (regular) sudokus and (wacky!) jigsaws.
The 2 '5-stars' jigsaws from the e-book are hardly that! Both are rated ED=3.0, needing a naked pair to solve.
As I recall, the free version of the app came with a number of jigsaw types, type 1 being 3Rx2C blocks.
For regular sixy sudokus, I posted a solver here.

The wacky jigsaws are essentially JSBs. I generated this a year ago:
Image
Code: Select all
.2........3.4.......6...........5... 111222113322413325443355446655466665

Analysis (without Generalized Intersections), ED=6.6: Show
26 x Hidden Single
1 x Direct Claiming
1 x Direct Hidden Pair
3 x Naked Single
6 x Pointing
4 x Claiming
2 x X-Wing
3 x XY-Wing
2 x XYZ-Wing
1 x Generalized X-Wing
2 x Forcing X-Chain

Analysis (with Generalized Intersections), ED=4.2: Show
28 x Hidden Single
1 x Direct Hidden Pair
2 x Naked Single
6 x Pointing
6 x Claiming
9 x Generalized Intersection
1 x X-Wing
1 x Hidden Pair
1 x XY-Wing

Here are some non-symmetric sixy jigsaws I made:
Image
Code: Select all
......3.....6....54....3......2...36 112333112334512434512444552266556666

Analysis, ED=4.2: Show
28 Hidden Single
2 Pointing
2 X-Wing
1 XY-Wing

Image
Code: Select all
....4...4.......2......15.....3..... 112222111123444423544333555663556666

Analysis, ED=6.6: Show
28 Hidden Single
2 Direct Claiming
2 Pointing
1 Claiming
1 X-Wing
1 XY-Wing
1 Turbot Fish

Finally, here is a real '5-star' hard sixy jigsaw:
Image
Code: Select all
......6..........1......3......5.2.. 122233111233141223444443555566556666

Analysis, ED=7.1: Show
30 Hidden Single
1 Naked Single
12 Pointing
7 Claiming
11 Generalized Intersection
4 Naked Pair
2 Naked Triplet
3 XY-Wing
1 XYZ-Wing
1 BUG type 2
1 Generalized X-Wing
1 Bidirectional Y-Cycle
1 Forcing Chain

Forum post: here, I posted a SixySolver: here. It will brute-force solve a sixy sudoku (including jigsaws).
1to9only
 
Posts: 3448
Joined: 04 April 2018

Re: ED=1.9/1.9/1.9 SixySudoku puzzle

Postby urhegyi » Fri Feb 05, 2021 5:47 pm

sixy.gen02.66.png
sixy.gen02.66.png (11.16 KiB) Viewed 223 times

I applied a few times the law of leftovers and a generalized form of remote pair and came to this
solution:
Hidden Text: Show
Code: Select all
263145
154362
415623
632451
541236
326514
urhegyi
 
Posts: 539
Joined: 13 April 2020

Re: ED=1.9/1.9/1.9 SixySudoku puzzle

Postby urhegyi » Sat Feb 06, 2021 5:00 pm

Solved thisone with x-wing and xy-wing:
sixy.gen01.42.png
sixy.gen01.42.png (11.23 KiB) Viewed 201 times

Solution:
Hidden Text: Show
Code: Select all
542361
361524
613245
425613
136452
254136
urhegyi
 
Posts: 539
Joined: 13 April 2020

Re: ED=1.9/1.9/1.9 SixySudoku puzzle

Postby urhegyi » Sat Feb 06, 2021 11:05 pm

I found a site with 60 examples of a SixyWacky sudoku generated by a maple package(source available)
https://sites.math.rutgers.edu/~zeilberg/Sixy/Problems.html
urhegyi
 
Posts: 539
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