| View previous topic :: View next topic   | 
	
	
	
		| Author | 
		Message | 
	
	
		Clement
 
 
  Joined: 24 Apr 2006 Posts: 1113 Location: Dar es Salaam Tanzania
  | 
		
			
				 Posted: Sat Jun 23, 2012 10:16 pm    Post subject: Jun 24 VH | 
				     | 
			 
			
				
  | 
			 
			
				| XY-Wing 57 78 58 pivoted in r3c8 solves it by setting r7c2<>5. | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		dongrave
 
 
  Joined: 06 Mar 2014 Posts: 572
 
  | 
		
			
				 Posted: Thu Mar 06, 2014 2:43 pm    Post subject: Jun 24 2012 VH | 
				     | 
			 
			
				
  | 
			 
			
				| I'm going back through the archive now to try to solve the VH ones.  How did you eliminate the candidate 5 from r3c8?  I had the candidates 578 instead of just 78 in r3c8 so I missed the XY wing.  Thanks. | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
  | 
		
			
				 Posted: Thu Mar 06, 2014 5:49 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				 	  | Code: | 	 		  
 
+--------------+--------+-------------+
 
| 16   8  56   | 7 15 9 | 4   3   2   |
 
| 17   3  2    | 4 6  8 | 159 579 579 |
 
| 4    57 9    | 3 15 2 | 158 578 6   |
 
+--------------+--------+-------------+
 
| 578  9  4    | 1 2  3 | 58  6   578 |
 
| 57   2  1    | 8 79 6 | 3   579 4   |
 
| 3678 67 3678 | 5 79 4 | 2   1   789 |
 
+--------------+--------+-------------+
 
| 9    56 568  | 2 4  1 | 7   58  3   |
 
| 37   4  37   | 9 8  5 | 6   2   1   |
 
| 2    1  58   | 6 3  7 | 589 4   589 |
 
+--------------+--------+-------------+
 
 | 	  
 
Play this puzzle online at the Daily Sudoku site
 
 
I don't know if I'm done with basics yet. But look at row 2. The 5s are restricted to row 2 in box 3, thus no other rows in that box can contain 5. | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		dongrave
 
 
  Joined: 06 Mar 2014 Posts: 572
 
  | 
		
			
				 Posted: Thu Mar 06, 2014 6:21 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				| Oh!  How obvious!  How did I miss that?  I actually still had a 5 in r1c1 and r2c1 even though I knew that r4c1 or r5c1 had to be a 5.  Thanks! | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		Marty R.
 
 
  Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
  | 
		
			
				 Posted: Thu Mar 06, 2014 9:00 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				| That situation in row 2 is called either Locked Candidates or Box-Line Interactions and are extremely easy to miss. Many people miss them, including myself. | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		 |