dailysudoku.com Forum Index dailysudoku.com
Discussion of Daily Sudoku puzzles
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

VH100617

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Other puzzles
View previous topic :: View next topic  
Author Message
arkietech



Joined: 31 Jul 2008
Posts: 1834
Location: Northwest Arkansas USA

PostPosted: Thu Oct 05, 2017 11:08 pm    Post subject: VH100617 Reply with quote

Code:
 *-----------*
 |.3.|6..|9..|
 |..9|...|.3.|
 |..7|.29|...|
 |---+---+---|
 |72.|.3.|...|
 |5..|.1.|..6|
 |...|.8.|.91|
 |---+---+---|
 |...|56.|8..|
 |.6.|...|4..|
 |..2|..4|.6.|
 *-----------*


Play/Print this puzzle online
Back to top
View user's profile Send private message
AjÚ Dimonios



Joined: 01 May 2017
Posts: 339
Location: Sassari Italy

PostPosted: Fri Oct 06, 2017 7:07 am    Post subject: Reply with quote

Hi everyone

Code:

+----------+------------+----------------+
| 2   3  5 | 6   4  178 | 9    178  78   |
| 46  18 9 | 178 5  178 | 1267 3    2478 |
| 46  18 7 | 3   2  9   | 16   1458 458  |
+----------+------------+----------------+
| 7   2  1 | 9   3  6   | 5    48   48   |
| 5   9  8 | 4   1  27  | 3    27   6    |
| 3   4  6 | 27  8  5   | 27   9    1    |
+----------+------------+----------------+
| 19  7  4 | 5   6  3   | 8    12   29   |
| 189 6  3 | 128 79 128 | 4    157  579  |
| 189 5  2 | 18  79 4   | 17   6    3    |
+----------+------------+----------------+

Play this puzzle online at the Daily Sudoku site
[(2)R5C8-(2=1)R7C8 and (2-7)R5C8=(7)R6C7-(7=1)R9C7]=>contradiction two singles 1 in box 9=>-2R5C8=>stte.

Ciao a tutti

Paolo
Back to top
View user's profile Send private message
ZeroAssoluto



Joined: 05 Feb 2017
Posts: 527
Location: Rimini, Italy

PostPosted: Fri Oct 06, 2017 7:19 am    Post subject: Reply with quote

Hi everyone,

Code:

+----------+------------+-------------+
| 2   3  5 | 6   4  18  | 9  178  78  |
| 46  18 9 | 178 5  178 | 26 3    24  |
| 46  18 7 | 3   2  9   | 16 1458 458 |
+----------+------------+-------------+
| 7   2  1 | 9   3  6   | 5  48   48  |
| 5   9  8 | 4   1  27  | 3  27   6   |
| 3   4  6 | 27  8  5   | 27 9    1   |
+----------+------------+-------------+
| 19  7  4 | 5   6  3   | 8  12   29  |
| 189 6  3 | 128 79 128 | 4  157  579 |
| 189 5  2 | 18  79 4   | 17 6    3   |
+----------+------------+-------------+

Play this puzzle online at the Daily Sudoku site

Quote:
XY-Wing 1,2,7 in r57c8,r9c7 and -7 in r6c7,r8c8
or
XY-Wing 1,2,7 in r69c7,r7c8 and -2 in r5c8


Ciao Gianni
Back to top
View user's profile Send private message
Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA

PostPosted: Fri Oct 06, 2017 8:47 pm    Post subject: Reply with quote

Code:

+----------+------------+-------------+
| 2   3  5 | 6   4  18  | 9  178  78  |
| 46  18 9 | 178 5  178 | 26 3    24  |
| 46  18 7 | 3   2  9   | 16 1458 458 |
+----------+------------+-------------+
| 7   2  1 | 9   3  6   | 5  48   48  |
| 5   9  8 | 4   1  27  | 3  27   6   |
| 3   4  6 | 27  8  5   | 27 9    1   |
+----------+------------+-------------+
| 19  7  4 | 5   6  3   | 8  12   29  |
| 189 6  3 | 128 79 128 | 4  157  579 |
| 189 5  2 | 18  79 4   | 17 6    3   |
+----------+------------+-------------+

Play this puzzle online at the Daily Sudoku site

UR (18)r89c1,r89c4

2r8c4=9r89c1-(9=1)r7c1-(1=2)r7c8-r5c8=r6c8=> -2r8c6
Back to top
View user's profile Send private message
immpy



Joined: 06 May 2017
Posts: 322

PostPosted: Sat Oct 07, 2017 1:13 am    Post subject: Reply with quote

Hello all.....

This is beautiful!!! Here again is another example of a UR with 9 on a common side r89c1. I realize there remains a 2 to be accounted for in r8c4, but the puzzle still solves by removing the 9 from r7c1, which is seen by both 9s in the rectangle side. Am I crazy, or what??? Works every time.

This move does not take the puzzle to the end. A W-Wing on 18 r2c4 and r8c6 with a strong link on 1 removes the 8 from r12c6 and r9c4. stte.

My argument would be that as long as ONE of those side squares will contain the 9, my elimination is sound. I cannot knock my success rate of 100% using the UR in this manner.

I must see a puzzle where this move doesn't work before I will abandon it.

immpy
Back to top
View user's profile Send private message
immpy



Joined: 06 May 2017
Posts: 322

PostPosted: Sat Oct 07, 2017 1:43 am    Post subject: Reply with quote

Hello all again...

I would suggest not using the UR in my misguided manner, if you are not comfortable doing so, logically speaking. I believe the 2 must somehow be accounted for, true, but "Vas kom a do?" That's an old PA Dutch phrase for "What can I do?" It has never failed me yet! Maybe I should suggest saving the move for an absolute last resort (when nothing else avails itself).
In my last posted puzzle, the UR would have never existed, had I used an XY-Wing earlier. And that is also the case here.

The XY-Wing of 127 pivoted at either r9c7 or r7c8 is enough to bring the puzzle to this point, which is identical to using my misguided UR side technique. As you can see, the UR no longer exists due to eliminations and solved squares.

Code:

+---------+-----------+--------------+
| 2  3  5 | 6  4  178 | 9   18   78  |
| 46 18 9 | 18 5  178 | 167 3    2   |
| 46 18 7 | 3  2  9   | 16  1458 458 |
+---------+-----------+--------------+
| 7  2  1 | 9  3  6   | 5   48   48  |
| 5  9  8 | 4  1  2   | 3   7    6   |
| 3  4  6 | 7  8  5   | 2   9    1   |
+---------+-----------+--------------+
| 1  7  4 | 5  6  3   | 8   2    9   |
| 89 6  3 | 2  79 18  | 4   15   57  |
| 89 5  2 | 18 79 4   | 17  6    3   |
+---------+-----------+--------------+

Play this puzzle online at the Daily Sudoku site

Now the W-Wing of 18 can be applied, as stated in a previous post.

Thank you arkietech for a beautiful scheme, and to all for your input.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Other puzzles All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group