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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Fri Jan 23, 2009 2:58 am    Post subject: Jan 23 VH |   |  
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				| Not your routine VH.  Two xy-wings (379 then 345) will solve it. Or a UR (45) followed by coloring (4).
 Anyone see a single-step solution?
 
 Earl
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Fri Jan 23, 2009 4:57 am    Post subject: |   |  
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				|  	  | Code: |  	  | +----------------+------------+----------------+
 | 1   247  478   | 9  237 348 | 48   6    5    |
 | 289 2467 46789 | 24 27  5   | 1    3    248  |
 | 5   24   3     | 6  1   48  | 9    248  7    |
 +----------------+------------+----------------+
 | 238 236  68    | 5  4   9   | 7    1    238  |
 | 7   1    45    | 3  8   2   | 45   9    6    |
 | 238 9    45    | 1  6   7   | 3458 2458 2348 |
 +----------------+------------+----------------+
 | 4   37   1     | 8  359 6   | 2    57   39   |
 | 39  8    2     | 7  359 34  | 6    45   1    |
 | 6   5    79    | 24 239 1   | 348  478  3489 |
 +----------------+------------+----------------+
 
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 Play this puzzle online at the Daily Sudoku site
 
 A four-cell XY-Chain starting with 4 in r8c6 and ending in r7c2 will create pincers on 3 in those two cells and that's all that was needed.
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		| cgordon 
 
 
 Joined: 04 May 2007
 Posts: 769
 Location: ontario, canada
 
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				|  Posted: Fri Jan 23, 2009 3:08 pm    Post subject: |   |  
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				| Wow!  A very hard that was actually very hard. 
 I used 4 steps after the quad in C3.  A UR for <45>;  a skyscraper on <4>; and two xy-wings <379> and <345>.
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		| Wendy W 
 
 
 Joined: 04 Feb 2008
 Posts: 144
 
 
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				|  Posted: Fri Jan 23, 2009 11:15 pm    Post subject: |   |  
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				| Gosh, I didn't think it was tough. I did exactly what Earl did (as per usual!), just the 2 quick xy-wings, and it fell apart. |  | 
	
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		| cgordon 
 
 
 Joined: 04 May 2007
 Posts: 769
 Location: ontario, canada
 
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				|  Posted: Sat Jan 24, 2009 12:55 am    Post subject: |   |  
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				| Wendy - and Earl - you are absolutely right.  Only two xy wings were needed. For me, Type 1 UR's (and skyscrapers) are so easy to identify - whereas xy or xyz wings are not "pattern friendly".
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		| Wendy W 
 
 
 Joined: 04 Feb 2008
 Posts: 144
 
 
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				|  Posted: Sat Jan 24, 2009 1:11 pm    Post subject: |   |  
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				| Isn't it funny how we have individual ways of solving a puzzle! I immediately look for xy-wings and xyz-wings, but just because I find searching for x-wings to be much more cumbersome. Not to get in another C vs. F debate, but is it any warmer up your way?
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		| cgordon 
 
 
 Joined: 04 May 2007
 Posts: 769
 Location: ontario, canada
 
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				|  Posted: Sat Jan 24, 2009 4:05 pm    Post subject: |   |  
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				| No. Yesterday it warmed up to 2C (28F) but today its 16C (3F) with a wind chill of 20C.  Just to counter an earlier argument, wind chill is important because of the 30-30-30 Rule: when exposed to a 30-m.p.h. wind at -30° F (-34C), human flesh freezes solid in 30 seconds. 
 Sudoku weather.
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sat Jan 24, 2009 4:57 pm    Post subject: |   |  
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				| Yesterday was 44° (F) and today's high will be about 15°. 
 
  	  | Quote: |  	  | I immediately look for xy-wings and xyz-wings, but just because I find searching for x-wings to be much more cumbersome. | 
 Same here. I look for everything else first and X-Wings as a last resort after all other avenues have been exhausted.
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		| DennyOR 
 
 
 Joined: 12 Sep 2007
 Posts: 33
 Location: Portland, Oregon
 
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				|  Posted: Mon Jan 26, 2009 11:01 pm    Post subject: |   |  
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				| And another solution is the 379 xy-wing followed by a 359 xyz-wing. |  | 
	
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