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Puzzle 10/03/18 Advanced

 
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Thu Mar 18, 2010 11:53 pm    Post subject: Puzzle 10/03/18 Advanced Reply with quote

Code:
 +-----------------------+
 | . . . | . . 9 | 3 8 . |
 | . 6 . | . . . | . . 9 |
 | . . 8 | 1 . . | 7 . 6 |
 |-------+-------+-------|
 | . . 7 | . . . | . . 1 |
 | . . . | . . 7 | . 3 . |
 | 8 . . | . 1 2 | . . . |
 |-------+-------+-------|
 | 7 . 6 | . . . | 1 . 2 |
 | 2 . . | . 9 . | . . 3 |
 | . 1 9 | 7 . . | 6 4 . |
 +-----------------------+

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Mogulmeister



Joined: 03 May 2007
Posts: 1151

PostPosted: Fri Mar 19, 2010 6:29 am    Post subject: Reply with quote

Quote:
1)There's a nice finned skyscraper on 5s with the fin at r3c1. Whether the fin is true or not, the 5 at r1c3 is eliminated.

2)At the same time, there is a simple xy chain, pincers at r8c3 and r1c9 which guarantees the removal of the 4 also in r1c3

It would have been nice to have been able to achieve steps 1&2 simultaneously by utilising the remote pair <45> at r8c3 & r2c7 as achieved in other daj Puzzle 10/03/17 ___ BBDB as VH+ unfortunately not this time. 5 at either pincer toggles 4 in the other but the same can not be said of 4 forcing a toggle to 5.

Much elimination follows but we’re not done.

3)Colouring removes a lot of 5s which completes this very nice puzzle.

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Marty R.



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

PostPosted: Sat Mar 20, 2010 4:44 pm    Post subject: Reply with quote

I am stuck after being able to do nothing more than an M-Wing on 45.

This has been, at least for me, the hardest DAJ puzzle in quite some time. I can see the finned skyscraper, but don't care to use them.

Code:

+----------------+-----------------+-----------+
| 1    7    25   | 245   6    9    | 3    8 45 |
| 345  6    2345 | 23458 7    3458 | 45   1 9  |
| 3459 3459 8    | 1     345  345  | 7    2 6  |
+----------------+-----------------+-----------+
| 349  2349 7    | 3489  348  6    | 2489 5 1  |
| 6    2459 1    | 4589  458  7    | 2489 3 48 |
| 8    3459 345  | 3459  1    2    | 49   6 7  |
+----------------+-----------------+-----------+
| 7    3458 6    | 3458  3458 3458 | 1    9 2  |
| 2    458  45   | 6     9    1    | 58   7 3  |
| 35   1    9    | 7     2    358  | 6    4 58 |
+----------------+-----------------+-----------+

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arkietech



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

PostPosted: Sat Mar 20, 2010 5:36 pm    Post subject: Reply with quote

Marty R. wrote:
I am stuck after being able to do nothing more than an M-Wing on 45.
Code:

+----------------+-----------------+-----------+
| 1    7    25   | 245   6    9    | 3    8 45 |
| 345  6    2345 | 23458 7    3458 | 45   1 9  |
| 3459 3459 8    | 1     345  345  | 7    2 6  |
+----------------+-----------------+-----------+
| 349  2349 7    | 3489  348  6    | 2489 5 1  |
| 6    2459 1    | 4589  458  7    | 2489 3 48 |
| 8    3459 345  | 3459  1    2    | 49   6 7  |
+----------------+-----------------+-----------+
| 7    3458 6    | 3458  3458 3458 | 1    9 2  |
| 2    458  45   | 6     9    1    | 58   7 3  |
| 35   1    9    | 7     2    358  | 6    4 58 |
+----------------+-----------------+-----------+

You can set the 2 in r1c3 with a fancy finned fish. Later look for remote pairs.
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Marty R.



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

PostPosted: Sat Mar 20, 2010 9:22 pm    Post subject: Reply with quote

Quote:
You can set the 2 in r1c3 with a fancy finned fish. Later look for remote pairs.

How fancy? I'm not too good on regular finned fish, not to mention fancy ones. At any rate, I assume the fish has to be 5s in order to set the cell=2. based on my limited understanding, I don't see a finned swordfish, jellyfish or squirmbag. Question
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Mogulmeister



Joined: 03 May 2007
Posts: 1151

PostPosted: Sat Mar 20, 2010 9:30 pm    Post subject: Reply with quote

The combination of the finned skyscraper then the M wing eliminates the 4 & 5 leaving 2. There's then a nice colouring on 5's which gets rid of a whole load of them.
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arkietech



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

PostPosted: Sat Mar 20, 2010 9:53 pm    Post subject: Reply with quote

Marty R. wrote:
How fancy? I'm not too good on regular finned fish, not to mention fancy ones. At any rate, I assume the fish has to be 5s in order to set the cell=2. based on my limited understanding, I don't see a finned swordfish, jellyfish or squirmbag. Question
Code:
+----------------+-----------------+-----------+
| 1    7    2-5  | 245   6    9    | 3    8f45 |
| 345  6    2345 | 23458 7    3458 |*45   1 9  |
| 3459 3459 8    | 1     345  345  | 7    2 6  |
+----------------+-----------------+-----------+
| 349  2349 7    | 3489  348  6    | 2489 5 1  |
| 6   *2459 1    | 4589  458  7    | 2489 3 48 |
| 8   *3459*345  | 3459  1    2    | 49   6 7  |
+----------------+-----------------+-----------+
| 7    3458 6    | 3458  3458 3458 | 1    9 2  |
| 2   *458 *45   | 6     9    1    |*58   7 3  |
| 35   1    9    | 7     2    358  | 6    4 58 |
+----------------+-----------------+-----------+
There is a finned Franken sword on 5 at r8b34 c237 the fin is at r1c9
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

PostPosted: Sat Mar 20, 2010 9:55 pm    Post subject: Reply with quote

Marty,

here is what I see: Grouped coloring on a skyscraper:
Code:
+-------------------+-------------------+-------------------+
| 1     7    2-5    | 245   6     9     | 3     8     45b   |
| 345a  6     2345  | 23458 7     3458  | 45    1     9     |
| 3459a 3459  8     | 1     345   345   | 7     2     6     |
+-------------------+-------------------+-------------------+
| 349   2349  7     | 3489  348   6     | 2489  5     1     |
| 6     2459  1     | 4589  458   7     | 2489  3     48    |
| 8     3459  345   | 3459  1     2     | 49    6     7     |
+-------------------+-------------------+-------------------+
| 7     358   6     | 3458  3458  3458  | 1     9     2     |
| 2     458   45    | 6     9     1     | 58    7     3     |
| 35A   1     9     | 7     2     358   | 6     4     58B   |
+-------------------+-------------------+-------------------+
Look at R9C19.

One or both of A or B is false (not 5). One of the cells a is true, and or b is true. Any cell that sees both cells a and the cell b cannot be 5.

After that, and some work, choose your poison: A BUG+1 or a classic remote pair.

Keith
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

PostPosted: Sat Mar 20, 2010 10:00 pm    Post subject: Reply with quote

Marty,

I suppose this is a finned skyscraper:
Code:
+-------------------+-------------------+-------------------+
| 1     7    2-5    | 245   6     9     | 3     8     45b   |
| 345c  6     2345  | 23458 7     3458  | 45    1     9     |
| 3459a 3459  8     | 1     345   345   | 7     2     6     |
+-------------------+-------------------+-------------------+
| 349   2349  7     | 3489  348   6     | 2489  5     1     |
| 6     2459  1     | 4589  458   7     | 2489  3     48    |
| 8     3459  345   | 3459  1     2     | 49    6     7     |
+-------------------+-------------------+-------------------+
| 7     358   6     | 3458  3458  3458  | 1     9     2     |
| 2     458   45    | 6     9     1     | 58    7     3     |
| 35A   1     9     | 7     2     358   | 6     4     58B   |
+-------------------+-------------------+-------------------+

Either the 5 skyscraper Aa-Bb is true, or c is true. Either way, R1C3 is not 5.

Keith
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Sat Mar 20, 2010 10:55 pm    Post subject: Reply with quote

Marty R. wrote:
I am stuck after being able to do nothing more than an M-Wing on 45.

This has been, at least for me, the hardest DAJ puzzle in quite some time. I can see the finned skyscraper, but don't care to use them.

Another perspective on the same pattern others have already mentioned. What you're missing is a Sashimi X-Wing where <5> is missing in r1c1 but counter-balanced by the presence of <5> in r23c1.

Code:
 Sashimi X-Wing c19\r19 w/fin cells r23c1  =>  r1c3<>5
 +-----------------------------------------------------------------------+
 |  1      7      2-5    |  245    6      9      |  3      8     *45     |
 | #345    6      2345   |  23458  7      3458   |  45     1      9      |
 | #3459   3459   8      |  1      345    345    |  7      2      6      |
 |-----------------------+-----------------------+-----------------------|
 |  349    2349   7      |  3489   348    6      |  2489   5      1      |
 |  6      2459   1      |  4589   458    7      |  2489   3      48     |
 |  8      3459   345    |  3459   1      2      |  49     6      7      |
 |-----------------------+-----------------------+-----------------------|
 |  7      3458   6      |  3458   3458   3458   |  1      9      2      |
 |  2      458    45     |  6      9      1      |  58     7      3      |
 | *35     1      9      |  7      2      358    |  6      4     *58     |
 +-----------------------------------------------------------------------+
 # 81 eliminations remain

As Keith mentioned, it's very much like a Skyscraper, but the presence of two candidates in r23c1 restricts any eliminations to the box containing them.
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Marty R.



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

PostPosted: Sat Mar 20, 2010 11:19 pm    Post subject: Reply with quote

Thank you for the responses. I'll have to check out Franken and Sashimi.

Quote:
Either the 5 skyscraper Aa-Bb is true, or c is true. Either way, R1C3 is not 5.

That one I follow but prefer not to use finned stuff.
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oaxen



Joined: 10 Jul 2006
Posts: 96

PostPosted: Sun Mar 21, 2010 12:08 pm    Post subject: Reply with quote

This was a good one! For me the fun with sudoko is to find the spot where I can make the game to be a one steper. I have a feeling all the puzzles have that opportunity!?
This time first in the second round i understood that one of the 3's in block G, namely in r7c2 is the winner.

Lars
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Sun Mar 21, 2010 8:09 pm    Post subject: Reply with quote

arkietech wrote:
Marty R. wrote:
How fancy? I'm not too good on regular finned fish, not to mention fancy ones. At any rate, I assume the fish has to be 5s in order to set the cell=2. based on my limited understanding, I don't see a finned swordfish, jellyfish or squirmbag. Question
Code:
+----------------+-----------------+-----------+
| 1    7    2-5  | 245   6    9    | 3    8f45 |
| 345  6    2345 | 23458 7    3458 |*45   1 9  |
| 3459 3459 8    | 1     345  345  | 7    2 6  |
+----------------+-----------------+-----------+
| 349  2349 7    | 3489  348  6    | 2489 5 1  |
| 6   *2459 1    | 4589  458  7    | 2489 3 48 |
| 8   *3459*345  | 3459  1    2    | 49   6 7  |
+----------------+-----------------+-----------+
| 7    3458 6    | 3458  3458 3458 | 1    9 2  |
| 2   *458 *45   | 6     9    1    |*58   7 3  |
| 35   1    9    | 7     2    358  | 6    4 58 |
+----------------+-----------------+-----------+
There is a finned Franken sword on 5 at r8b34 c237 the fin is at r1c9


Dan, I also had a problem getting this puzzle started. I am familiar with finned, Kraken and sashimi fish but simply failed to see the step on 5s.

However, I do not understand a Franken fish. I studied the pattern you identified but still don't understand the thing. Please provide the details.

Ted
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arkietech



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

PostPosted: Sun Mar 21, 2010 9:06 pm    Post subject: Reply with quote

tlanglet wrote:
Dan, I also had a problem getting this puzzle started. I am familiar with finned, Kraken and sashimi fish but simply failed to see the step on 5s.

However, I do not understand a Franken fish. I studied the pattern you identified but still don't understand the thing. Please provide the details.

first if the fin r1c9 is 5 then r1c3 <>5
if r2c7 is not 5 then r1c1 or r1c3 is 5 and r1c3<>5
if r2c7 is 5 then r8c7 is not 5 and r8c2 or r8c3 is 5
if r8c2 then r6c3 is 5 and r1c3<>5
if r8c3=5 then r1c3<>5

Hope this helps.
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Sun Mar 21, 2010 11:07 pm    Post subject: Reply with quote

Alternate perspective of finned Franken Swordfish r8b34\c237 w/fin r1c9

Consider the candidate cells in [r8]

Code:
(5): r8c2 - r56c2 = r6c3 - r1c3   [b4] used as link in elimination
(5): r8c3                - r1c3
(5): r8c7 - r2c7  = r1c9 - r1c3   [b3] used as link in elimination

[c237] contains ever cell used except r1c9
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