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		| RobertRattley 
 
 
 Joined: 24 Jun 2007
 Posts: 118
 Location: Australia
 
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				|  Posted: Thu Apr 11, 2013 10:11 pm    Post subject: Apr 12 VH |   |  
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				| OK:  for once, Australia beats Tanzania. 
 But I won't spell it out.  Just my summary.
 
 One step, xy wing.
 
 I enjoyed this puzzle.  I needed intermediate-to-hard steps both before and after the xy wing.
 
 I'll let somebody else reveal a fuller solution and I look forward to seeing what alternatives others may find.
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		| Clement 
 
 
 Joined: 24 Apr 2006
 Posts: 1113
 Location: Dar es Salaam Tanzania
 
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				|  Posted: Thu Apr 11, 2013 11:04 pm    Post subject: Apr 12 VH |   |  
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				| RobertRattley, O.K. Congratulations.
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Fri Apr 12, 2013 1:02 am    Post subject: |   |  
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				| Same as you Robert, an XY-Wing. What made this puzzle different from most is that there were a lot of numbers in the grid. I screwed up with pencil and paper and had to do it on Draw/Play to see if I had a wrong grid or made a mechanical error. As it turned out I had the right grid but erred on the remaining basics after playing the XY-Wing. |  | 
	
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		| kuskey 
 
 
 Joined: 10 Dec 2008
 Posts: 141
 Location: Pembroke, NH
 
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				|  Posted: Fri Apr 12, 2013 5:06 am    Post subject: Apr 12 VH |   |  
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				| A 125 xyz wing contered at r6c1 sets r6c3<>2 yielding a solution after some rather nice cleanup. Some would argue the use of an xyz as a VH tool, I guess. |  | 
	
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		| hughwill 
 
 
 Joined: 05 Apr 2010
 Posts: 424
 Location: Birmingham UK
 
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				|  Posted: Fri Apr 12, 2013 9:24 am    Post subject: |   |  
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				| These were my basics...they didn't seem to go very far today..... 
 
  	  | Code: |  	  | +-----------+--------------------+-----------------+
 | 7   4  59 | 23589  2389  2358  | 6     139  139  |
 | 6   2  1  | 7      349   34    | 39    5    8    |
 | 3   8  59 | 569    1     56    | 4     2    7    |
 +-----------+--------------------+-----------------+
 | 25  9  8  | 1      235   7     | 23    6    4    |
 | 4   16 7  | 2368   2368  2368  | 1239  1389 5    |
 | 125 3  26 | 4      2568  9     | 7     18   12   |
 +-----------+--------------------+-----------------+
 | 128 7  3  | 2589   2489  2458  | 1259  19   6    |
 | 9   5  26 | 236    7     1     | 8     4    23   |
 | 128 16 4  | 235689 23689 23568 | 12359 7    1239 |
 +-----------+--------------------+-----------------+
 
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 Play this puzzle online at the Daily Sudoku site
 
 
 As far as I know xyzs are fine for solving VHs. Good spot over the
 more obvious(?) xy.
 
 Hugh (another lazy morning in the Western Hemisphere...)
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		| RobertRattley 
 
 
 Joined: 24 Jun 2007
 Posts: 118
 Location: Australia
 
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				|  Posted: Fri Apr 12, 2013 7:01 pm    Post subject: |   |  
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				| Thanks, Hugh, for posting the grid. 
 Those were my basics too.  And my xy-wing was a 126 with fulcrum box 4 cell 9, pinching box 4 cell 7 on 1.  (See!  I use a different notation!  How perverse of me.)
 
 Good spot, kuskey.  I didn't see that xyz wing.  And, assuredly, xyz wings do "count" equally.  Virtually by definition, a "very hard" puzzle on this site is one that needs, and can be solved by, one or more x-wings, xy-wings or xyz-wings.  Not to imply that it's "wrong" to use some other technique - whatever solves the puzzle.
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		| viiiknow 
 
 
 Joined: 13 Apr 2013
 Posts: 1
 
 
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				|  Posted: Sat Apr 13, 2013 6:51 am    Post subject: |   |  
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				| Thank you all. This is one deviously delicious puzzle. |  | 
	
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