| View previous topic :: View next topic   | 
	
	
	
		| Author | 
		Message | 
	
	
		Clement
 
 
  Joined: 24 Apr 2006 Posts: 1113 Location: Dar es Salaam Tanzania
  | 
		
			
				 Posted: Thu Aug 05, 2021 9:57 am    Post subject: Aug 05 VH | 
				     | 
			 
			
				
  | 
			 
			
				 	  | Code: | 	 		  
 
+-------------------+-----------------+-------------------+
 
| 6      2      4   | 9      5      7 | 8      1       3  |
 
| 57     8      57  | 4      1      3 | 9      6       2  |
 
| 1      3      9   | 8      6      2 | 5      7       4  |
 
+-------------------+-----------------+-------------------+
 
| 8     a79     567 | 3      27     1 | 4      259    b69 |
 
| 2      1      6-7 | 5      4      9 |c67     3       8  |
 
| 59     4      3   | 6      27     8 | 27     59      1  |
 
+-------------------+-----------------+-------------------+
 
| 79     6      8   | 27     3      4 | 1      29      5  |
 
| 3      79     1   | 27     8      5 | 26     4       69 |
 
| 4      5      2   | 1      9      6 | 3      8       7  |
 
+-------------------+-----------------+-------------------+
 
 | 	  
 
XY-Wing: (7=9)r4c2 - (9=6)r4c9 - (6=7)r5c7 => - 7r5c3; stte | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		TomC
 
 
  Joined: 30 Oct 2020 Posts: 359 Location: Wales
  | 
		
			
				 Posted: Thu Aug 05, 2021 10:24 am    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				| I used the very similar 679 XY to remove the 6's in r4c3 and r5c7 | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		TomC
 
 
  Joined: 30 Oct 2020 Posts: 359 Location: Wales
  | 
		
			
				 Posted: Thu Aug 05, 2021 12:22 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				Another way, r4c8<>2
 
 
If you stick to the cells in row 4 and box 6 this would give either two 7's in box 6 or two 7's in row 4 | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		Mogulmeister
 
 
  Joined: 03 May 2007 Posts: 1151
 
  | 
		
			
				 Posted: Thu Aug 05, 2021 12:29 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				 	  | TomC wrote: | 	 		  Another way, r4c8<>2
 
 | 	  
 
 
Or....via pincers for 2 at r4c5 and r7c8. | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		Mogulmeister
 
 
  Joined: 03 May 2007 Posts: 1151
 
  | 
		
			
				 Posted: Thu Aug 05, 2021 12:36 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				| (2=9)r7c8-(9=7)r7c1-(7=9)r8c2-(9=7)r4c2-(7=2)r4c5 => r4c8<>2 | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		TomC
 
 
  Joined: 30 Oct 2020 Posts: 359 Location: Wales
  | 
		
			
				 Posted: Thu Aug 05, 2021 1:05 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				Or using the XY cells abc in Clement's grid
 
 
r6c7<> 7 as then no 7's box 5 | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		Mogulmeister
 
 
  Joined: 03 May 2007 Posts: 1151
 
  | 
		
			
				 Posted: Fri Aug 06, 2021 3:03 pm    Post subject:  | 
				     | 
			 
			
				
  | 
			 
			
				| Yes  - Clement's xy wing layout at abc also shows that whatever the value in a(r4c2) the value of c (r5c7) is always 7 and so r6c7 must be <> 7. | 
			 
		  | 
	
	
		| Back to top | 
		 | 
	
	
		  | 
	
	
		 |