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 

Jan. 11 vh

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Daily Sudoku puzzles
View previous topic :: View next topic  
Author Message
nataraj



Joined: 03 Aug 2007
Posts: 1048
Location: near Vienna, Austria

PostPosted: Fri Jan 11, 2008 7:55 am    Post subject: Jan. 11 vh Reply with quote

Happy New Year ! (I know, I know, the new year has been around for a while, but I haven't ... Smile )

After basics, look for an x-wing (9) which exposes an xy-wing (16-46-14 in the upper right area). There is another xy-wing (36-39-69, again in the upper right) which solves the puzzle.

I did not use the UR (36) that had been staring in my face for some time, so maybe that would have been more direct.
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Johan



Joined: 25 Jun 2007
Posts: 206
Location: Bornem Belgium

PostPosted: Fri Jan 11, 2008 9:25 am    Post subject: Reply with quote

There is a 4-cell xy-chain (A,B,C,D) present in the grid that solves the puzzle in one fell swoop. Both pincer ends in R3C2(A) and R1C9(D) can see digit <6> in R1C2, so <6> can be eliminated in R1C2.

The 4-cell xy-chain : [69-93-34-46]
Code:

+--------------------------+--------------------------+--------------------------+
| 78         5-[6]     78  | 356         9        1   | 2        C 34      D 46  |
| 25         3         29  | 56          8        4   | 169        7         169 |
| 1        A 69        4   | 36          7        2   | 8        B 39        5   |
+--------------------------+--------------------------+--------------------------+
| 9          78        3   | 48          2        57  | 145        6         14  |
| 6          4         5   | 1           3        9   | 7          2         8   |
| 78         2         1   | 48          6        57  | 459        49        3   |
+--------------------------+--------------------------+--------------------------+
| 4          78        78  | 9           1        36  | 36         5         2   |
| 23         1         29  | 7           5        36  | 3469       8         469 |
| 35         59        6   | 2           4        8   | 39         1         7   |
+--------------------------+--------------------------+--------------------------+
Back to top
View user's profile Send private message Send e-mail
ravel



Joined: 21 Apr 2006
Posts: 536

PostPosted: Fri Jan 11, 2008 11:09 am    Post subject: Reply with quote

Code:
+--------------------------+--------------------------+--------------------------+
|#78         56       #78  | 356         9        1   | 2          34        46  |
| 25         3         29  | 56          8        4   | 169        7         169 |
| 1          69        4   | 36          7        2   | 8          39        5   |
+--------------------------+--------------------------+--------------------------+
| 9         #78        3   |#48          2       #57  |#145        6         14  |
| 6          4         5   | 1           3        9   | 7          2         8   |
|#78         2         1   |#48          6       #57  |#459        49        3   |
+--------------------------+--------------------------+--------------------------+
| 4         #78       #78  | 9           1        36  | 36         5         2   |
| 23         1         29  | 7           5        36  | 3469       8         469 |
| 35         59        6   | 2           4        8   | 39         1         7   |
+--------------------------+--------------------------+--------------------------+
I like this deadly pattern (with 45 in r46c7), which allows to eliminate 4 from r46c7, but it does not solve the puzzle (neither the 36 UR).
Back to top
View user's profile Send private message
George Woods



Joined: 28 Mar 2006
Posts: 304
Location: Dorset UK

PostPosted: Fri Jan 11, 2008 11:53 am    Post subject: W Wing solution Reply with quote

Code:

+------------+----------+-------------+
| 578  56 78 | 356 9 1  | 2    34 46  |
| 25  3   29 | 56  8 4  | 169  7  169 |
| 1   69  4  | 36  7 2  | 8    39 5   |
+------------+----------+-------------+
| 9   78  3  | 458 2 57 | 145  6  14  |
| 6   4   5  | 1   3 9  | 7    2  8   |
| 78  2   1  | 458 6 57 | 459  49 3   |
+------------+----------+-------------+
| 4   78  78 | 9   1 36 | 36   5  2   |
| 23  1   29 | 7   5 36 | 3469 8  469 |
| 35  59  6  | 2   4 8  | 39   1  7   |
+------------+----------+-------------+

[url=http://www.dailysudoku.com/sudoku/play.shtml?p=578: 56:78:356:9:1:2:34:46:25:3:29:56:8:4:169:7:169:1:69:4:36:7:2:8:39:5:9:78:3:458:2:57:145:6:14:6:4:5:1:3:9:7:2:8:78:2:1:458:6:57:459:49:3:4:78:78:9:1:36:36:5:2:23:1:29:7:5:36:3469:8:469:35:59:6:2:4:8:39:1:7:]Play this puzzle online[/url] at the Daily Sudoku site

Having reached this point ( using draw/play sweep and correcting only r1c2) :-


I reckon the W-Wing 56 in Boxes 1 and 2 operating on row 3 solves it!
Back to top
View user's profile Send private message
cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Fri Jan 11, 2008 3:58 pm    Post subject: Reply with quote

Took me forever to get through the basics - couldn't even see the naked pairs. Is that a sign of old age? Eventually used the same UR (36) and x-wing on 9's that Nataraj mentioned. But still needed an xyz-wing for <169> (C79) for the coup-de-grace.
Back to top
View user's profile Send private message
nataraj



Joined: 03 Aug 2007
Posts: 1048
Location: near Vienna, Austria

PostPosted: Fri Jan 11, 2008 6:22 pm    Post subject: Reply with quote

could someone (George or a moderator) please edit George Woods' post and insert one or two blanks into this line "56:78:356:9:1:2:34..." so that the text will fit on my screen again ?

pleeeze ...

Smile
Back to top
View user's profile Send private message Send e-mail Visit poster's website
George Woods



Joined: 28 Mar 2006
Posts: 304
Location: Dorset UK

PostPosted: Sat Jan 12, 2008 12:15 am    Post subject: W Wing solution Reply with quote

nataraj wrote:
could someone (George or a moderator) please edit George Woods' post and insert one or two blanks into this line "56:78:356:9:1:2:34..." so that the text will fit on my screen again ?

pleeeze ...

Smile


This text should have been suppressed _ being the code to generate the green matrix - and adds nothing to the substance of the message!

If someone could tell me how to get (as once I used to) a copy from "asci" in draw/play that ends up with an active "play this ...." I would be very grateful
Back to top
View user's profile Send private message
Marty R.



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

PostPosted: Sat Jan 12, 2008 1:12 am    Post subject: Reply with quote

Quote:
If someone could tell me how to get (as once I used to) a copy from "asci" in draw/play that ends up with an active "play this ...." I would be very grateful
_________________
George woods


1) Click Ascii to the right of the grid
2) Click in the middle part of the new window so it gets highlighted
3) Copy it (Ctrl+C)
4) Paste it (Ctrl+V) into the message box

Hope this helps.

Code:

+------------------+------------------+------------------+
| 578  45678 478   | 356   9    1     | 2      34   46   |
| 125  3     129   | 56    8    4     | 169    7    169  |
| 178  46789 14789 | 36    367  2     | 134689 1349 5    |
+------------------+------------------+------------------+
| 9    478   13478 | 13458 1237 3578  | 145    6    124  |
| 6    4     5     | 134   123  39    | 7      1249 8    |
| 178  2     1478  | 14568 167  56789 | 1459   1459 3    |
+------------------+------------------+------------------+
| 4    578   2378  | 9     136  368   | 1356   1235 1267 |
| 23   1     239   | 7     5    36    | 3469   8    2469 |
| 3578 5789  6     | 2     4    38    | 1359   1359 179  |
+------------------+------------------+------------------+

Play this puzzle online at the Daily Sudoku site
Back to top
View user's profile Send private message
storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Sat Jan 12, 2008 6:29 am    Post subject: Reply with quote

put me down for:

the UR on 36, takes out {3,6} in r8c7

then x-wing on 9 takes out a couple nines, most importantly the 9 in r2c7

which opened the xy-wing pincers in r2c7 and r4c9 taking out 1 in r2c9, solves the puzzle.

and I like johan's solution. very nice

the number of {7,8} pairs was ridiculous

happy new year nataraj,

Norm
Back to top
View user's profile Send private message
ledzepxx



Joined: 03 Jun 2008
Posts: 3

PostPosted: Tue Jun 03, 2008 12:54 pm    Post subject: Reply with quote

hey everyone, first time posting here
been going through old VHs, trying to improve
anyway, i'm stuck at this stage
could someone point out where to go from here?
Code:

+--------------+-----------+---------------+
| 578  56  478 | 356 9 1   | 2    34  46   |
| 25   3   29  | 56  8 4   | 169  7   169  |
| 1    69  49  | 36  7 2   | 8    349 5    |
+--------------+-----------+---------------+
| 9    78  3   | 48  2 57  | 145  6   14   |
| 6    4   5   | 1   3 9   | 7    2   8    |
| 78   2   1   | 48  6 57  | 459  49  3    |
+--------------+-----------+---------------+
| 4    78  278 | 9   1 368 | 36   5   267  |
| 23   1   29  | 7   5 36  | 3469 8   2469 |
| 3578 59  6   | 2   4 38  | 39   1   79   |
+--------------+-----------+---------------+
Back to top
View user's profile Send private message
cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Tue Jun 03, 2008 1:32 pm    Post subject: Reply with quote

Welcome ledzepxx. You didn't get far enough with basics. Note the pair of 29's in C3 - that will get you to the UR mentioned above.

Good Luck,
Craig
Back to top
View user's profile Send private message
ledzepxx



Joined: 03 Jun 2008
Posts: 3

PostPosted: Tue Jun 03, 2008 2:06 pm    Post subject: Reply with quote

cgordon wrote:
Welcome ledzepxx. You didn't get far enough with basics. Note the pair of 29's in C3 - that will get you to the UR mentioned above.

Good Luck,
Craig

thanks
could you explain UR too Embarassed
Back to top
View user's profile Send private message
cgordon



Joined: 04 May 2007
Posts: 769
Location: ontario, canada

PostPosted: Tue Jun 03, 2008 3:30 pm    Post subject: Reply with quote

See the four 36’s in R78 C67 - you can remove the 36 in R8C7. I’m not the guy to explain why – so if you haven’t gotten into URs I would recommend visiting
http://www.sudoku.com/boards/viewtopic.php?p=29105#29105
written by Keith. There are I believe 6 different UR types and their logic is related to unique solutions and “Deadly Patterns” Just remember (cos I often forget) the pattern has to be in two parallel boxes – not four.


Code:
               
+-------+--------+---------+   
| . . . | . . 36 | 36  .  .|   
| . . . | . . 36 | 3649.  .|   
| . . . | . . .  | .   .  .|
+-------+--------+---------+


Code:
               
+-------+--------+---------+   
| . . . | . . 36 | 36  .  .|   
| . . . | . . 36 | 49  .  .|   
| . . . | . . .  | .   .  .|
+-------+--------+---------+
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Daily Sudoku 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