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Local Paper Puzzle

 
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leocar



Joined: 04 Mar 2010
Posts: 8

PostPosted: Fri May 14, 2010 10:46 am    Post subject: Local Paper Puzzle Reply with quote

Hi,

below is where I got with basics (further below is the original puzzle) but can't get any further. The puzzle is out of a local paper. The grader says itís too difficult, is this true and itís a miss print or is it just too hard for the solver? Thank you

Leo

Code:

+-------------+------------+----------------+
| 5   3  689  | 2   18 7   | 169   16  4    |
| 79  27 1    | 49  6  349 | 5     23  8    |
| 69  4  2689 | 5   18 39  | 12369 7   1369 |
+-------------+------------+----------------+
| 3   69 5    | 169 7  8   | 16    4   2    |
| 4   8  7    | 16  5  2   | 136   9   136  |
| 2   1  69   | 3   4  69  | 8     5   7    |
+-------------+------------+----------------+
| 19  5  29   | 46  23 46  | 7     8   139  |
| 167 27 3    | 8   9  5   | 4     126 16   |
| 8   69 4    | 7   23 1   | 2369  236 5    |
+-------------+------------+----------------+


Original puzzle
Code:

+-------+-------+-------+
| . . . | 2 . 7 | . . 4 |
| . . 1 | . 6 . | 5 . . |
| . 4 . | . . . | . 7 . |
+-------+-------+-------+
| 3 . . | . . 8 | . . 2 |
| . 8 . | . 5 . | . 9 . |
| 2 . . | 3 . . | . . 7 |
+-------+-------+-------+
| . 5 . | . . . | . 8 . |
| . . 3 | . 9 . | 4 . . |
| 8 . . | 7 . 1 | . . . |
+-------+-------+-------+
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Mogulmeister



Joined: 03 May 2007
Posts: 703

PostPosted: Fri May 14, 2010 11:22 am    Post subject: Reply with quote

Hi leocar,

You're actually not too far away and it seems that your solver is out of whack or you have turned something off!

From your last position look for an X-Wing on 2s.......then just one step more and you will be done.
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leocar



Joined: 04 Mar 2010
Posts: 8

PostPosted: Fri May 14, 2010 11:41 am    Post subject: Reply with quote

Is it the 2 in R9C8 which is eliminated leaving 36 but I can't see the next step. Much to my frustration! Is there another X wing that I'm missing?[/quote]
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Mogulmeister



Joined: 03 May 2007
Posts: 703

PostPosted: Fri May 14, 2010 1:31 pm    Post subject: Reply with quote

Yes that's the one.

Then, depends what you do next but I favour a simple XY Chain which will take out the 2 at r7c5. Smile

Hope that helps.
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Kdelle



Joined: 20 Mar 2008
Posts: 59
Location: Hudson, NH

PostPosted: Fri May 14, 2010 5:26 pm    Post subject: Reply with quote

After the X wing 2, the w wing 23 in boxes 3 and 8, with the strong link on 2 in c7 eliminates the 3 in r9c8....leaving only the 6 in that position.
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Mogulmeister



Joined: 03 May 2007
Posts: 703

PostPosted: Fri May 14, 2010 5:45 pm    Post subject: Reply with quote

So there you are leo - depends what you prefer!
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Steve R



Joined: 24 Oct 2005
Posts: 289
Location: Birmingham, England

PostPosted: Fri May 14, 2010 8:26 pm    Post subject: Reply with quote

Kathyís neat W-wing does the trick all on its own.

Steve
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Fri May 14, 2010 8:42 pm    Post subject: Reply with quote

Here's another approach.

Code:
 X-Wing in <2> followed by Naked Pair <69> and other basics
 *--------------------------------------------------------------------*
 | 5      369    689    | 2      18     7      | 1369   136    4      |
 | 79    *2379   1      | 49     6      349    | 5     *23     8      |
 | 69     4      2689   | 5      18     39     | 12369  7      1369   |
 |----------------------+----------------------+----------------------|
 | 3      69     5      | 169    7      8      | 16     4      2      |
 | 4      8      7      | 16     5      2      | 136    9      136    |
 | 2      1      69     | 3      4      69     | 8      5      7      |
 |----------------------+----------------------+----------------------|
 | 19     5      29     | 46     23     46     | 7      8      139    |
 | 167   *267    3      | 8      9      5      | 4     *126    16     |
 | 8      69-2   4      | 7      23     1      | 2369   36-2   5      |
 *--------------------------------------------------------------------*

Code:
 after X-Wing in <2> and more basics: 2-String Kite in <9>
 *--------------------------------------------------------------------*
 | 5      3      689*   | 2      18     7      | 169*   16     4      |
 | 79     27     1      | 49     6      349    | 5      23     8      |
 | 69     4      2689   | 5      18     39     | 12369  7      1369*  |
 |----------------------+----------------------+----------------------|
 | 3      69     5      | 169    7      8      | 16     4      2      |
 | 4      8      7      | 16     5      2      | 136    9      136    |
 | 2      1      69     | 3      4      69     | 8      5      7      |
 |----------------------+----------------------+----------------------|
 | 19     5      2-9    | 46     23     46     | 7      8      139*   |
 | 167    27     3      | 8      9      5      | 4      126    16     |
 | 8      69     4      | 7      23     1      | 2369   36     5      |
 *--------------------------------------------------------------------*
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Mogulmeister



Joined: 03 May 2007
Posts: 703

PostPosted: Fri May 14, 2010 8:42 pm    Post subject: Reply with quote

Steve, according to Kathy, just like the xy chain, It needs the X wing first otherwise there is no strong link on 2s in c7.
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leocar



Joined: 04 Mar 2010
Posts: 8

PostPosted: Sat May 15, 2010 4:15 am    Post subject: Reply with quote

Thank you for the responses. I think I have the W-Wing worked out (I hope). So if the start is the R2C8 23 then linked to the 2 in R3C7, then linked to the 2 in R9C7 and ending with the 23 in R9C5. Now since R9C8 links both the 23's, the 3 can be eliminated, is that correct?

Code:

+-------------+------------+----------------+
| 5   3  689  | 2   18 7   | 169   16  4    |
| 79  27 1    | 49  6  349 | 5     @23  8    |
| 69  4  2689 | 5   18 39  | @12369 7   1369 |
+-------------+------------+----------------+
| 3   69 5    | 169 7  8   | 16    4   2    |
| 4   8  7    | 16  5  2   | 136   9   136  |
| 2   1  69   | 3   4  69  | 8     5   7    |
+-------------+------------+----------------+
| 19  5  29   | 46  23 46  | 7     8   139  |
| 167 27 3    | 8   9  5   | 4     126 16   |
| 8   69 4    | 7   @23 1   | @2369  *36  5    |
+-------------+------------+----------------+
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Marty R.



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

PostPosted: Sat May 15, 2010 5:03 am    Post subject: Reply with quote

leocar wrote:
Thank you for the responses. I think I have the W-Wing worked out (I hope). So if the start is the R2C8 23 then linked to the 2 in R3C7, then linked to the 2 in R9C7 and ending with the 23 in R9C5. Now since R9C8 links both the 23's, the 3 can be eliminated, is that correct?

Code:

+-------------+------------+----------------+
| 5   3  689  | 2   18 7   | 169   16  4    |
| 79  27 1    | 49  6  349 | 5     @23  8    |
| 69  4  2689 | 5   18 39  | @12369 7   1369 |
+-------------+------------+----------------+
| 3   69 5    | 169 7  8   | 16    4   2    |
| 4   8  7    | 16  5  2   | 136   9   136  |
| 2   1  69   | 3   4  69  | 8     5   7    |
+-------------+------------+----------------+
| 19  5  29   | 46  23 46  | 7     8   139  |
| 167 27 3    | 8   9  5   | 4     126 16   |
| 8   69 4    | 7   @23 1   | @2369  *36  5    |
+-------------+------------+----------------+

I think a more conventional wording would be that the two 23 cells are connected by a strong link on 2 in c7. If r3c7=2, then r2c8=3. If r9c7=2, then r9c5=3. Since at least one of the 23 cells must be=3, the 3s act as pincers, eliminating the 3 from r9c8.
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Steve R



Joined: 24 Oct 2005
Posts: 289
Location: Birmingham, England

PostPosted: Sat May 15, 2010 12:26 pm    Post subject: Reply with quote

MM

Itís of minimal interest but, for what itís worth, I also got straight to Leoís grid in the very first post with its conjugates for 2 in column 7.

Steve
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Mogulmeister



Joined: 03 May 2007
Posts: 703

PostPosted: Sat May 15, 2010 8:25 pm    Post subject: Reply with quote

Yes - I was confused by the remark to Kathy. The X wing is not needed.
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