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NoChain -- Set A -- Puzzle 9

 
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Mon Oct 13, 2008 5:32 am    Post subject: NoChain -- Set A -- Puzzle 9 Reply with quote

I don't know if this puzzle is appropriate or not. Familiar technique habits may not help.

Code:
 +-----------------------+
 | 5 8 . | . . . | . . . |
 | 4 . . | . . . | 1 . . |
 | . . 1 | . . 8 | 5 . 7 |
 |-------+-------+-------|
 | . . . | 9 . . | 6 1 5 |
 | . . . | . . . | . . 2 |
 | . . 4 | . . 1 | 8 . . |
 |-------+-------+-------|
 | . 6 9 | 1 . 3 | 4 . 8 |
 | . . . | 2 . . | . 5 . |
 | . . 5 | 8 4 . | 2 . 9 |
 +-----------------------+   # NC_Set_A #9
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Asellus



Joined: 05 Jun 2007
Posts: 865
Location: Sonoma County, CA, USA

PostPosted: Mon Oct 13, 2008 8:36 am    Post subject: Reply with quote

A 6-cell DP creates a binary pseudo-cell that serves as one end of a W-Wing and solves the puzzle in one step.

It can also be solved in about 4 steps with commonly used techniques.
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cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Mon Oct 13, 2008 1:17 pm    Post subject: Reply with quote

After the basic quad in R5, I found an ER on 6; a skyscraper on 6; and an x-wing on 7. Looks like there could be an xy or xyz wing out there but I can't find one. So right now I'm stuck.
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tlanglet



Joined: 17 Oct 2007
Posts: 2461
Location: Northern California Foothills

PostPosted: Mon Oct 13, 2008 1:48 pm    Post subject: Reply with quote

Asellus wrote:
A 6-cell DP creates a binary pseudo-cell that serves as one end of a W-Wing and solves the puzzle in one step.

It can also be solved in about 4 steps with commonly used techniques.

Fantastic solution Exclamation Exclamation Exclamation


Here is the code I had after basics.
Code:
 
*-----------------------------------------------------------*
 | 5     8     2367  | 367   1     26    | 9     23    4     |
 | 4     2379  237   | 357   379   259   | 1     8     6     |
 | 369   239   1     | 4     369   8     | 5     23    7     |
 |-------------------+-------------------+-------------------|
 | 378   237   2378  | 9     378   4     | 6     1     5     |
 | 19    19    368   | 356   368   56    | 7     4     2     |
 | 67    5     4     | 67    2     1     | 8     9     3     |
 |-------------------+-------------------+-------------------|
 | 2     6     9     | 1     5     3     | 4     7     8     |
 | 78    4     78    | 2     69    69    | 3     5     1     |
 | 13    13    5     | 8     4     7     | 2     6     9     |
 *-----------------------------------------------------------*


I started off with a UR <78> but then realized that the deletion was also removed by the following swordfish (or x-wing) on <7>, then a skyscraper on <6> and a w-wing <23>. But at this point, I am also stuck; will try again later with fresh eyes .....

Ted
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Mon Oct 13, 2008 8:22 pm    Post subject: Reply with quote

Code:
.------------------.------------------.------------------.
| 5     8     2367 | 367   1     26   | 9     23    4    |
| 4     2379  237  | 357   379   259  | 1     8     6    |
| 369   239   1    | 4     369   8    | 5     23    7    |
:------------------+------------------+------------------:
| 378   237   2378 | 9     378   4    | 6     1     5    |
| 19    19    368  | 356   368   56   | 7     4     2    |
| 67    5     4    | 67    2     1    | 8     9     3    |
:------------------+------------------+------------------:
| 2     6     9    | 1     5     3    | 4     7     8    |
| 78    4     78   | 2     69    69   | 3     5     1    |
| 13    13    5    | 8     4     7    | 2     6     9    |
'------------------'------------------'------------------'


skyscraper
x-wing
xyz-wing
xy-wing
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nataraj



Joined: 03 Aug 2007
Posts: 1029
Location: Vienna, Austria

PostPosted: Mon Oct 13, 2008 8:29 pm    Post subject: Reply with quote

After basics,

Code:

+--------------------------+--------------------------+--------------------------+
| 5       8       2367#    | 367#    1       26       | 9       23      4        |
| 4       2379    237      | 357     379     259      | 1       8       6        |
| 369     239     1        | 4       369     8        | 5       23      7        |
+--------------------------+--------------------------+--------------------------+
| 378     237     2378     | 9       378     4        | 6       1       5        |
| 19      19      368*     | 35-6    3-68    5-6      | 7       4       2        |
| -67     5       4        | 67*     2       1        | 8       9       3        |
+--------------------------+--------------------------+--------------------------+
| 2       6       9        | 1       5       3        | 4       7       8        |
| 78      4       78       | 2       69      69       | 3       5       1        |
| 13      13      5        | 8       4       7        | 2       6       9        |
+--------------------------+--------------------------+--------------------------+


a (generalized) m-wing (6)r6c4=r5c3 via sl (7) in row 1; r6c1,r5c456<>6

solves the puzzle in one step.

---

(edited twice: once to add "generalized" to the m-wing, and then - seeing Asellus' post right after mine, to add this "edited" paragraph)


Last edited by nataraj on Mon Oct 13, 2008 8:53 pm; edited 2 times in total
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Asellus



Joined: 05 Jun 2007
Posts: 865
Location: Sonoma County, CA, USA

PostPosted: Mon Oct 13, 2008 8:30 pm    Post subject: Reply with quote

The <7> fish reveals a useful XYZ Wing.

If anyone is curious, the DP is on 139 in c13. The pseudo-binary is {26} in r3c12, forming a W-Wing with r1c6 via the <2>s in c8 and removing <6> from r1c3.
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nataraj



Joined: 03 Aug 2007
Posts: 1029
Location: Vienna, Austria

PostPosted: Mon Oct 13, 2008 8:42 pm    Post subject: Reply with quote

very elegant solution, Asellus, to use the 26 virtual cell as one end of a w-wing! Something to remember, for sure. I usually only scan for immediate naked-pair-type eliminations ...

_________

on an unrelated topic:
499 is not the end, I hope !
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ravel



Joined: 21 Apr 2006
Posts: 536

PostPosted: Tue Oct 14, 2008 8:24 pm    Post subject: Reply with quote

nataraj wrote:
on an unrelated topic:
499 is not the end, I hope !
Hehe, i was not aware of this number.
It's just, that i am a bit short of time and - at the first - short of good ideas. Always when i tried a puzzle here recently, i already found a solution, that was at least as good as mine.
Such puzzles containing a nugget, which Asellus found here, are not posted here and there every month - tributs to Danny also.
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nataraj



Joined: 03 Aug 2007
Posts: 1029
Location: Vienna, Austria

PostPosted: Tue Oct 14, 2008 8:41 pm    Post subject: Reply with quote

great! "we" passed the magic one Very Happy

being a bit short on time myself, this place feels like one of those bars where you drop in at the end of a busy day and get transported to another universe ... (I seem to remember there was a bar like that in Key West) and, sometimes, a challenging puzzle to make my day Smile
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Tue Oct 14, 2008 11:07 pm    Post subject: Reply with quote

Quote:
I seem to remember there was a bar like that in Key West


the cantina in star wars? sorry, its the most rediculous thought that came to mind.
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