| View previous topic :: View next topic |
| Author |
Message |
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
 Posted: Tue Mar 17, 2009 1:01 pm Post subject: Set Z_01 Puzzle 14 -- Salsa ? |
 |
|
If you miss the XY-Chain, then you may need a GPS tracker to find your sanity.
| Code: | +-----------------------+
| 1 . . | . . . | . . . |
| . . . | . 1 . | 4 5 . |
| . . . | . 6 2 | . 8 1 |
|-------+-------+-------|
| . . . | 5 . 9 | . . 7 |
| . 9 2 | . 8 . | . . . |
| . . 7 | 1 . . | 9 . 4 |
|-------+-------+-------|
| . 4 . | . . 1 | . . . |
| . 2 5 | . . . | . . . |
| . . 9 | 8 . 4 | . . 5 |
+-----------------------+
|
Play this puzzle online at the Daily Sudoku site |
|
| Back to top |
|
 |
storm_norm
Joined: 18 Oct 2007
Posts: 1741
|
| Posted: Tue Mar 17, 2009 9:49 pm Post subject: |
|
|
Danny,
did you post the board correctly?
this puzzle has a 7.6 SE rating.
I have found a ER on 6
skyscraper on 6
m-wing via grouped link.
then it stops. |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Tue Mar 17, 2009 9:58 pm Post subject: |
|
|
| storm_norm wrote: | Danny,
did you post the board correctly?
this puzzle has a 7.6 SE rating.
I have found a ER on 6
skyscraper on 6
m-wing via grouped link.
then it stops. |
This puzzle has the ?? sink included in its solution. You still have at least one more W-Wing and two Uniqueness tests to resolve ... and then you're still not done getting around the XY-Chain. Enjoy!!! |
|
| Back to top |
|
|
storm_norm
Joined: 18 Oct 2007
Posts: 1741
|
| Posted: Tue Mar 17, 2009 10:35 pm Post subject: |
|
|
| Code: | .------------------.------------------.------------------.
| 1 M367 8 |-3479 -3479 5 |M367 M3679 2 |
| 2 367 36 | 379 1 8 | 4 5 369 |
| 9 5 4 |M37 6 2 |M37 8 1 |
:------------------+------------------+------------------:
| 346 36 1 | 5 234 9 | 8 236 7 |
| 346 9 2 | 3467 8 367 | 5 1 36 |
| 5 8 7 | 1 23 36 | 9 236 4 |
:------------------+------------------+------------------:
| 3678 4 36 | 2 5 1 | 367 3679 3689 |
| 378 2 5 | 3679 379 367 | 1 4 38 |
| 367 1 9 | 8 37 4 | 2 367 5 |
'------------------'------------------'------------------' |
marked above is the M-wing on {3,7} eliminates the 3's in r1c45
ER 6 removes 6 from r4c8
skyscraper 6 removes 6 from r1c2 and r2c9
| Code: | .------------------.------------------.------------------.
| 1 37 8 | 479 479 5 | 367 3679 2 |
| 2 367 36 | 379 1 8 | 4 5 39 |
| 9 5 4 | 37 6 2 | 37 8 1 |
:------------------+------------------+------------------:
| 346 36 1 | 5 234 9 | 8 23 7 |
| 34 9 2 | 467 8 367 | 5 1 36 |
| 5 8 7 | 1 23 36 | 9 236 4 |
:------------------+------------------+------------------:
| 3678 4 36 | 2 5 1 | 367 3679 3689 |
| 378 2 5 | 679 379 367 | 1 4 38 |
| 367 1 9 | 8 37 4 | 2 367 5 |
'------------------'------------------'------------------' |
UR {2,3}r46c58 says that neither the 4 in r4c5 or the 6 in r6c8 can both be false.
UR23[(4)r4c5 = (6)r6c8] - (6=3)r5c9 - (3=4)r5c1; r5c4 <> 4
some singles.
| Code: | .------------------.------------------.------------------.
| 1 37 8 | 4 *79 5 | 367 3679 2 |
| 2 367 36 |*379 1 8 | 4 5 *39 |
| 9 5 4 | 37 6 2 | 37 8 1 |
:------------------+------------------+------------------:
| 36 36 1 | 5 4 9 | 8 2 7 |
| 4 9 2 | 67 8 3-67 | 5 1 *36 |
| 5 8 7 | 1 2 *36 | 9 *36 4 |
:------------------+------------------+------------------:
| 3678 4 36 | 2 5 1 | 367 3679 -3689 |
| 378 2 5 |6-79 *379 *67 | 1 4 -38 |
| 367 1 9 | 8 *37 4 | 2 367 5 |
'------------------'------------------'------------------' |
nice loop
(3=9)r2c9 - (9)r2c4 = (9-7)r1c5 = (7)r89c5 - (7=6)r8c6 - (6)r6c6  = (6)r6c8 - (6=3)r5c9; r78c9 <> 3
but I also believe it means r8c4 is not 7 and r5c6 is not 6
which solves the puzzle after a naked pair. |
|
| Back to top |
|
|
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Wed Mar 18, 2009 3:01 pm Post subject: |
|
|
After two days of working on this puzzle, I am putting it on the shelf to complete another day. I tried all my non-chain steps without completing it and my chain techniques are almost non-existent.
Like Norm, I started with the ER and skyscraper on <6>, and then worked on the UR23. However, I saw the UR as a Type 6 diagonal with a x-wing2 overlay that deleted <2> from r4c5 & r6c8. After that, I found a w-wing37 in r1c2 & r3c4 with a strong link <7> in row2 that deleted <3> from r1c45.
At this point I really struggled and found what I best describe as a "finned w-wing" or a "w-wing with a finned strong link" Here is the code: | Code: |
*-----------------------------------------------------------*
| 1 37 8 | 479 479 5 | 367 3679 2 |
| 2 367 36 | 379 1 8 | 4 5 39 |
| 9 5 4 | 37 6 2 | 37 8 1 |
|-------------------+-------------------+-------------------|
| 3-46 36 1 | 5 W34 9 | 8 2 7 |
| W34 9 2 | 3467 8 367 | 5 1 36 |
| 5 8 7 | 1 2 36 | 9 36 4 |
|-------------------+-------------------+-------------------|
| 3678 4 36 | 2 5 1 | 367 3679 3689 |
| 378 2 5 | 3679 379 367 | 1 4 38 |
| S367 1 9 | 8 S37 4 | 2 F367 5 |
*-----------------------------------------------------------* |
The w-wing34 (marked W) are in r4c5 & r5c1. Now look at row9; it has three cells containing <3>. Cells r9c1 & r9c5 act as strong links (marked S) for the w-wing, and the additional <3> in r9c8 is like a fin (marked F). If the strong link is true, then the w-wing makes deletes the <4> in r4c1. If the fin is true: (3)r9c8 - (3)r6c8 = (3)r5c9 - (3=4)r5c1; r4c1<>4.
Comments all .......
Ted
P.S. Did I mention I was getting desparate? |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Wed Mar 18, 2009 3:32 pm Post subject: |
|
|
| tlanglet wrote: | | P.S. Did I mention I was getting desparate? |
Did I mention there's a Sashimi X-Wing on <3> that seems to be important, but only to get you to the next roadblock?
PS: Congratulations to you and Norm for finding the UR 23! It's just before the two W-Wings. |
|
| Back to top |
|
|
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Wed Mar 18, 2009 3:56 pm Post subject: |
|
|
| daj95376 wrote: |
Did I mention there's a Sashimi X-Wing on <3> that seems to be important, but only to get you to the next roadblock?
|
At what stage is the Sashimi x-wing present?
Ted |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Wed Mar 18, 2009 4:53 pm Post subject: |
|
|
| tlanglet wrote: | | daj95376 wrote: |
Did I mention there's a Sashimi X-Wing on <3> that seems to be important, but only to get you to the next roadblock?
|
At what stage is the Sashimi x-wing present?
|
I have two solutions for this puzzle. My solver found and used the Sashimi X-Wing reasonably early. The HoDoKu solver used it near the end. It's present in your PM above. Once you find it, you'll go OOOOhhhhhh!!! |
|
| Back to top |
|
|
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Wed Mar 18, 2009 5:27 pm Post subject: |
|
|
I am going OOOOhhhhhh!!! And OOOOhhhhhh!!!
Best of all, this solved the puzzle. OOOOhhhhhh!!!
Ted  |
|
| Back to top |
|
|
wapati
Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.
|
| Posted: Thu Mar 19, 2009 4:14 am Post subject: |
|
|
I used a skyscraper on 6s followed by a finned-x-wing on 3s, of the sashimi sort but with a fin.
The UR on 23 then there are several finishes.
A remote 36 pair sets up an ER on 3s for the finish, or you could do an ER on 3s and then a skyscraper on 3s.
Fun puzzle, much easier for me than the other Z one! I did use xy-chains for it. |
|
| Back to top |
|
|
Marty R.
Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
|
| Posted: Wed Apr 01, 2009 9:02 pm Post subject: |
|
|
| I used a half-dozen moves before I got stuck and had to turn to Medusa. A trap set up a W-Wing and Remote Pairs for the finish. I needed three strong links to connect the W-Wing. |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Wed Apr 01, 2009 9:07 pm Post subject: |
|
|
Marty: I respect your perseverance on solving this and other puzzles.  |
|
| Back to top |
|
|
oaxen
Joined: 10 Jul 2006
Posts: 96
|
| Posted: Thu Apr 02, 2009 3:45 pm Post subject: |
|
|
Why so many complicated techniques? I just like to follow a thread after the basics and it never fails. In this puzzle we have 3 and 6 in r2c3 and r7c3. OK, try the 6 in r7c3 and after a short while it is obvious that instead 6 in r2c3 is correct. Means anyhow a lot of easy eliminations and some new numbes in the cells. But int his puzzle after a while there is a new final stop. However I try now with e.g. 7 in r1c2. With my bare eyes I now can see there soon will be a new final stop. means 7 in r1c8 must be correct. New eliminations follow, but as this is a hard puzzle I need a third start and choose 6 in r5c9. wrong. Means that 6 in r7c9 is correct and now I can follow the thread to a happy end. Normally I need only one or two attempts. May be here also if I in the first place hade made a cleverer choice where in a row, column or block I can find a number only represented twice.
Sometimes happens that the stop is not final, there are two more choices to do. I make a subthread and if in that the two alternatives goes to a final stop I am back again to the original thread, where alternative two must be correct. Heureka. |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Thu Apr 02, 2009 5:03 pm Post subject: |
|
|
| oaxen wrote: | Why so many complicated techniques? I just like to follow a thread after the basics and it never fails. In this puzzle we have 3 and 6 in r2c3 and r7c3. OK, try the 6 in r7c3 and after a short while it is obvious that instead 6 in r2c3 is correct. Means anyhow a lot of easy eliminations and some new numbes in the cells. But int his puzzle after a while there is a new final stop. However I try now with e.g. 7 in r1c2. With my bare eyes I now can see there soon will be a new final stop. means 7 in r1c8 must be correct. New eliminations follow, but as this is a hard puzzle I need a third start and choose 6 in r5c9. wrong. Means that 6 in r7c9 is correct and now I can follow the thread to a happy end. Normally I need only one or two attempts. May be here also if I in the first place hade made a cleverer choice where in a row, column or block I can find a number only represented twice.
Sometimes happens that the stop is not final, there are two more choices to do. I make a subthread and if in that the two alternatives goes to a final stop I am back again to the original thread, where alternative two must be correct. Heureka. |
Obviously, you tested the wrong <36> cells!
| Code: | after basics: [r6c6] = <36> => [r6c6]=3 cracks puzzle
*-----------------------------------------------------------*
| 1 367 8 | 3479 3479 5 | 367 3679 2 |
| 2 367 36 | 379 1 8 | 4 5 369 |
| 9 5 4 | 37 6 2 | 37 8 1 |
|-------------------+-------------------+-------------------|
| 346 36 1 | 5 234 9 | 8 236 7 |
| 346 9 2 | 3467 8 367 | 5 1 36 |
| 5 8 7 | 1 23 36 | 9 236 4 |
|-------------------+-------------------+-------------------|
| 3678 4 36 | 2 5 1 | 367 3679 3689 |
| 378 2 5 | 3679 379 367 | 1 4 38 |
| 367 1 9 | 8 37 4 | 2 367 5 |
*-----------------------------------------------------------*
|
|
|
| Back to top |
|
|
oaxen
Joined: 10 Jul 2006
Posts: 96
|
| Posted: Thu Apr 02, 2009 7:21 pm Post subject: |
|
|
Never mind. to make it little more sientific I played this puzzle twice and that time started from the other cell. It gives the same result in the end but this time I needed a subthread, because I was blocked little later.
What´s your opinion about my method? Why does it never fail? |
|
| Back to top |
|
|
oaxen
Joined: 10 Jul 2006
Posts: 96
|
| Posted: Thu Apr 02, 2009 7:28 pm Post subject: |
|
|
sorry I forgot to write
I can´t start with r6c6 because in that case I have three "3" alternatives in the row, in the column as well in the block |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Thu Apr 02, 2009 10:48 pm Post subject: |
|
|
| oaxen wrote: | sorry I forgot to write
I can´t start with r6c6 because in that case I have three "3" alternatives in the row, in the column as well in the block |
There are only two candidate in [r6c6] to consider. Since your method is based on exhaustively testing alternative possibilities, testing a cell's candidates meets your method.
As for your method, it goes by many names ... and they all fall into the Trial & Error category. If you're satisfied with this approach, then that's all that matters. |
|
| Back to top |
|
|
oaxen
Joined: 10 Jul 2006
Posts: 96
|
| Posted: Mon Apr 06, 2009 8:26 pm Post subject: |
|
|
| daj95376 wrote: | | oaxen wrote: | sorry I forgot to write
I can´t start with r6c6 because in that case I have three "3" alternatives in the row, in the column as well in the block |
There are only two candidate in [r6c6] to consider. Since your method is based on exhaustively testing alternative possibilities, testing a cell's candidates meets your method.
As for your method, it goes by many names ... and they all fall into the Trial & Error category. If you're satisfied with this approach, then that's all that matters. |
In every game there are rules to be followed. If my technique is against the rules then I am not happy. "Trial and error" you write. But all the other methods also are trials to find the right spot to start eliminate. I also understand from the other writers in this forum, that they are all guessing. If so, my method is not worser or better from a moral point of view. Or is the meaning with Sudoko to find complicated ways to solve the puzzle. As the germans say "Warum soll man eine Sache einfach machen, wenn alles sich so schön komplizieren lässt" |
|
| Back to top |
|
|
wapati
Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.
|
|
| Back to top |
|
|
Marty R.
Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
|
| Posted: Tue Apr 07, 2009 4:00 am Post subject: |
|
|
| oaxen wrote: | | daj95376 wrote: | | oaxen wrote: | sorry I forgot to write
I can´t start with r6c6 because in that case I have three "3" alternatives in the row, in the column as well in the block |
There are only two candidate in [r6c6] to consider. Since your method is based on exhaustively testing alternative possibilities, testing a cell's candidates meets your method.
As for your method, it goes by many names ... and they all fall into the Trial & Error category. If you're satisfied with this approach, then that's all that matters. |
In every game there are rules to be followed. If my technique is against the rules then I am not happy. "Trial and error" you write. But all the other methods also are trials to find the right spot to start eliminate. I also understand from the other writers in this forum, that they are all guessing. If so, my method is not worser or better from a moral point of view. Or is the meaning with Sudoko to find complicated ways to solve the puzzle. As the germans say "Warum soll man eine Sache einfach machen, wenn alles sich so schön komplizieren lässt" |
Hey, it's only a game, so to speak. These puzzles are available for our own amusement to do with what we please. The only rule is that each row, column and box end up with each number with no duplicates. And I'm unaware of any moral considerations with these puzzles unless you're in a competition playing on your own honor.
You can argue that other techniques are trial-and-error as well, but everybody has their own definition. As Danny said, if you're satisfied, that's all that counts. But you're not going to convince everyone that they're all guessing with the various techniques that are used. |
|
| Back to top |
|
|
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
