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Sue de Coq training

 
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ravel



Joined: 21 Apr 2006
Posts: 536

PostPosted: Mon Nov 03, 2008 6:27 pm    Post subject: Sue de Coq training Reply with quote

This current game pattern not only has many jellyfish puzzles, but also Sue de Coq's. I seldom look for them (and only find easy ones), but here it is highly recommended. Some examples for Sue de Coq's with a bivalue cell:
Code:

 . . 1 . . . 2 . .
 . 3 . 4 . 2 . 5 .
 6 . . . . . . . 3
 . 1 . 7 . 6 . 4 .
 . . . . . . . . .
 . 6 . 8 . 4 . 9 .
 7 . . . . . . . 5
 . 4 . 3 . 7 . 8 .
 . . 8 . . . 6 . .  m_b_metcalf

+-------------------------+-------------------------+-------------------------+
| 4589    5789    1       | 569     356789  3589    | 2      @67      489-67  |
|#89      3       7-9     | 4       167-89  2       |@17+89   5      @167+89  |
| 6       25789   24579   | 159     15789   1589    | 1489-7 @17      3       |
+-------------------------+-------------------------+-------------------------+
| 23589   1       2359    | 7       2359    6       | 358     4       28      |
| 234589  25789   234579  | 1259    12359   1359    | 13578   12367   12678   |
| 235     6       2357    | 8       1235    4       | 1357    9       127     |
+-------------------------+-------------------------+-------------------------+
| 7       29      2369    | 1269    124689  189     | 1349    123     5       |
| 1259    4       2569    | 3       12569   7       | 19      8       129     |
| 12359   259     8       | 1259    12459   159     | 6       1237    12479   |
+-------------------------+-------------------------+-------------------------+

If you split r2c79 into the 167 and 89 parts, its obvious, that one of the cells must be 8 or 9 - otherwise there are only 3 numbers 167 left for the 4 @-cells. And not both can be 8 and 9, so 167 are bound to the @-cells in the box.
So 89 can be eliminated from the rest of row 2 and 167 from the rest of box 3.

Code:
 . . 1 | . . . | 2 . .
 . 3 . | 4 . 5 | . 6 .
 5 . . | . . . | . . 7
-------+-------+-------
 . 6 . | 5 . 4 | . 7 .
 . . . | . . . | . . .
 . 7 . | 8 . 9 | . 2 .
-------+-------+-------
 3 . . | . . . | . . 9
 . 9 . | 6 . 1 | . 4 .
 . . 8 | . . . | 5 . .  JPF

+-------------------------+-------------------------+-------------------------+
| 46789   48      1       | 379     36789   3678    | 2       3589    3458    |
| 2789    3       279     | 4       12789   5       | 189     6       18      |
| 5       248     2469    | 1239    123689  2368    | 13489   1389    7       |
+-------------------------+-------------------------+-------------------------+
| 1289    6       239     | 5       123     4       | 1389    7       138     |
| 12489   12458   23459   | 1237    12367   2367    | 134689  13589   134568  |
| 14      7       345     | 8       136     9       | 1346    2       13456   |
+-------------------------+-------------------------+-------------------------+
| 3       1245    24567   | 27      24578   278     | 1678    18      9       |
|#27      9       257     | 6       23578   1       | 378     4       238     |
| 12467   124     8       | 2379    23479   237     | 5       13      1236    |
+-------------------------+-------------------------+-------------------------+

A very similar Sue de Coq here with the 27 in r8c1, solves it with "normal" advanced techniques.

Code:
. . 1 . . . 9 . .
. 2 . 1 . 3 . 4 .
4 . . . . . . . 7
. 8 . 7 . 1 . 5 .
. . . . . . . . .
. 3 . 2 . 9 . 7 .
8 . . . . . . . 1
. 6 . 5 . 2 . 9 .
. . 7 . . . 3 . . gsf

After the Sue de Coq, later i needed a transported generalized M-wing.

Code:
 . . 1 . . . 2 . .
 . 3 . 2 . 4 . 5 .
 6 . . . . . . . 4
 . 6 . 7 . 3 . 8 .
 . . . . . . . . .
 . 8 . 1 . 2 . 3 .
 9 . . . . . . . 5
 . 1 . 3 . 5 . 2 .
 . . 7 . . . 8 . .  m_b_metcalf

Sue de Coq, jellyfish, finned x-wing bring some progress - but still not finished yet.
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Asellus



Joined: 05 Jun 2007
Posts: 865
Location: Sonoma County, CA, USA

PostPosted: Mon Nov 03, 2008 9:26 pm    Post subject: Reply with quote

The Sud de Coq in that last puzzle is very interesting and powerful. I don't believe I've encountered one quite like it before.

Here is my solution path:
[1] Sue de Coq
[2] 4 X-Wing c48
[3] 9 Jellyfish r2468
[4] 6 Finned X-Wing r19

Which brings us here:
Code:
+----------+------------------+-----------------+
| 4  9  1  | 5     3    @67   | 2     67    8   |
| 7  3  8  | 2    #19-6  4    |c169   5    c169 |
| 6  2  5  | 89    178   1789 | 3     179   4   |
+----------+------------------+-----------------+
| 1  6  49 | 7     459   3    | 459   8     2   |
| 3  7  2  | 4689  568   689  | 156   1469  16  |
| 5  8  49 | 1     469   2    | 4679  3     679 |
+----------+------------------+-----------------+
| 9  4  3  |a68    2    @17f8 | 167   167   5   |
| 8  1  6  | 3     479   5    | 479   2     79  |
| 2  5  7  | 469  @16    169  | 8    b1469  3   |
+----------+------------------+-----------------+

[5] Finned XY-Wing
The potential XY-Wing is marked @, with Fin <8> marked "f" in r7c6. If the Fin is true, r7c4 is <6>, which the victim "#" can see via the ERs in boxes 9 and 3 ("transport path" marked "b" and "c").

This leads to:
Code:
+----------+-------------------+-----------------+
| 4  9  1  | 5     3     6     | 2     7     8   |
| 7  3  8  | 2   d@19    4     | 169   5     169 |
| 6  2  5  |c89    178  #789-1 | 3     19    4   |
+----------+-------------------+-----------------+
| 1  6  49 | 7     459   3     | 459   8     2   |
| 3  7  2  | 4689  568  @89    | 156   1469  16  |
| 5  8  49 | 1     469   2     | 4679  3     679 |
+----------+-------------------+-----------------+
| 9  4  3  |b68    2    @18f7  |a167  a16    5   |
| 8  1  6  | 3     479   5     | 479   2     79  |
| 2  5  7  | 469  #6-1   19    | 8     1469  3   |
+----------+-------------------+-----------------+

[6] Finned XY-Wing
Again marked @ with Fin <7> in r7c6. The Fin creates an ALS chain marked "abcd" resulting in r2c5=1 if the Fin is true. Since this is one of the XY-Wing pincers, its victims, #, are eliminated.
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ravel



Joined: 21 Apr 2006
Posts: 536

PostPosted: Tue Nov 04, 2008 1:06 pm    Post subject: Reply with quote

In the second finned xy-wing, isn't r9c6 the second pincer (making it an "almost triple") and the fin giving a third one in r2c5 ?
Nice solution anyway.

Here is another example with an even easier Sue de Coq - only 3 cells (with 2 other numbers) in the box.
Code:
+-------+-------+-------+
| 1 . . | . . . | . . 2 |
| . 2 . | . 3 . | . 4 . |
| . . 5 | 2 . 6 | 7 . . |
+-------+-------+-------+
| . . 4 | 3 . 8 | 9 . . |
| . . . | . 6 . | . . . |
| . . 6 | 9 . 1 | 2 . . |
+-------+-------+-------+
| . . 1 | 4 . 3 | 6 . . |
| . 5 . | . 9 . | . 3 . |
| 4 . . | . . . | . . 8 |
+-------+-------+-------+ Mauricio
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Asellus



Joined: 05 Jun 2007
Posts: 865
Location: Sonoma County, CA, USA

PostPosted: Tue Nov 04, 2008 6:52 pm    Post subject: Reply with quote

ravel wrote:
In the second finned xy-wing, isn't r9c6 the second pincer (making it an "almost triple") and the fin giving a third one in r2c5 ?

Oops! I'm sure I wasn't thinking of the c6 ALS as the "almost XY Wing," so can't account for it. Embarassed

However, as you note, it is still valid (lucky for me!) since it is an ALS chain:
ALS:r579c6[(1)r79c6=(7)r7c6] - ALS[(7)r7c7=(6)r7c78] - (6=8)r7c4 - (8=9)r3c4 - (9=1)r2c5

I like how the Sue de Coq in this puzzle induced a conjugate pair of <8>s in r2c13, perpendicular to the column (c2) containing the ALS outside of box 1. That is the situation I don't recall ever seeing before in a Sue de Coq. I've encountered several where the conjugate pair (or locked candidates) is induced parallel to the "external" ALS, however.

[What happened to all the other posts on this thread?]

[Edit to add "(or locked candidates)" since that's what is actually being induced by a Sue de Coq.]


Last edited by Asellus on Tue Nov 04, 2008 7:13 pm; edited 1 time in total
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Marty R.



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

PostPosted: Tue Nov 04, 2008 7:05 pm    Post subject: Reply with quote

Quote:
[What happened to all the other posts on this thread?]


??? I didn't touch anything.
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Tue Nov 04, 2008 9:01 pm    Post subject: Reply with quote

Asellus wrote:
[What happened to all the other posts on this thread?]

If you are referring to my posts, I deleted them to reconsider what I wanted to say.

I don't understand how a Sue de Coq works, but I've run several puzzles through my solver and observed that many had short continuous loops confined to two boxes and have some overlapping eliminations. Upon closer examination, I noticed a secondary relationship.

Here is ravel's first PM. Notice [r2c13]=789 and [r2c3]=3. An ALS (?) pair of bivalue cells in a mini-unit, along with a solved cell, is easy to spot and easy to test.

Code:
 ravel's PM
 +--------------------------------------------------------------------------------+
 |  4589    5789    1       |  569     356789  3589    |  2       67      46789   |
 |  89      3       79      |  4       16789   2       |  1789    5       16789   |
 |  6       25789   24579   |  159     15789   1589    |  14789   17      3       |
 |--------------------------+--------------------------+--------------------------|
 |  23589   1       2359    |  7       2359    6       |  358     4       28      |
 |  234589  25789   234579  |  1259    12359   1359    |  13578   12367   12678   |
 |  235     6       2357    |  8       1235    4       |  1357    9       127     |
 |--------------------------+--------------------------+--------------------------|
 |  7       29      2369    |  1269    124689  189     |  1349    123     5       |
 |  1259    4       2569    |  3       12569   7       |  19      8       129     |
 |  12359   259     8       |  1259    12459   159     |  6       1237    12479   |
 +--------------------------------------------------------------------------------+

If we eliminate the common candidate and set [r2c1]=8 and [r2c3]=7, then we get an immediate contradiction in [c2]. An immediate contradiction in an intersecting row/column -- or the mini-unit box -- is important to make this approach appealing to hand solvers.

Code:
 After making incorrect assignments
 *-----------------------------------------------------------------------------*
 | 459     59      1       | 569     356789  3589    | 2       67      46789   |
 | 8       3       7       | 4       169     2       | 19      5       169     |
 | 6       259     2459    | 159     15789   1589    | 14789   17      3       |
 |-------------------------+-------------------------+-------------------------|
 | 2359    1       2359    | 7       2359    6       | 358     4       28      |
 | 23459   259+78  23459   | 1259    12359   1359    | 13578   12367   12678   |
 | 235     6       235     | 8       1235    4       | 1357    9       127     |
 |-------------------------+-------------------------+-------------------------|
 | 7       29      2369    | 1269    124689  189     | 1349    123     5       |
 | 1259    4       2569    | 3       12569   7       | 19      8       129     |
 | 12359   259     8       | 1259    12459   159     | 6       1237    12479   |
 *-----------------------------------------------------------------------------*

This means that one of [r2c1]=9 or [r2c3]=9 must be true, and results in the following eliminations.

Code:
 eliminations in (9)
 +--------------------------------------------------------------------------------+
 |  458-9   578-9   1       |  569     356789  3589    |  2       67      46789   |
 |  89      3       79      |  4       1678-9  2       |  178-9   5       1678-9  |
 |  6       2578-9  2457-9  |  159     15789   1589    |  14789   17      3       |
 |--------------------------+--------------------------+--------------------------|
 |  23589   1       2359    |  7       2359    6       |  358     4       28      |
 |  234589  25789   234579  |  1259    12359   1359    |  13578   12367   12678   |
 |  235     6       2357    |  8       1235    4       |  1357    9       127     |
 |--------------------------+--------------------------+--------------------------|
 |  7       29      2369    |  1269    124689  189     |  1349    123     5       |
 |  1259    4       2569    |  3       12569   7       |  19      8       129     |
 |  12359   259     8       |  1259    12459   159     |  6       1237    12479   |
 +--------------------------------------------------------------------------------+

Note: This is only an observation of a relationship that occurs in some Sue de Coq puzzles.
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ravel



Joined: 21 Apr 2006
Posts: 536

PostPosted: Tue Nov 04, 2008 9:35 pm    Post subject: Reply with quote

Marty R. wrote:
I didn't touch anything.
Oh, they always say it ! Suddenly it (the car, the PC, the elevator, the TV, the parachute) did not work any more. I didn't touch anything. How unbelievable Twisted Evil

But luckily you are rehabilitated by Danny's interesting post.
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Marty R.



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

PostPosted: Tue Nov 04, 2008 10:09 pm    Post subject: Reply with quote

Quote:
But luckily you are rehabilitated by Danny's interesting post.


VINDICATION IS SWEET!! Laughing
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Wed Nov 05, 2008 1:14 am    Post subject: Reply with quote

Code:
+-------+-------+-------+
| 1 . . | . . . | . . 2 |
| . 2 . | . 3 . | . 4 . |
| . . 5 | 2 . 6 | 7 . . |
+-------+-------+-------+
| . . 4 | 3 . 8 | 9 . . |
| . . . | . 6 . | . . . |
| . . 6 | 9 . 1 | 2 . . |
+-------+-------+-------+
| . . 1 | 4 . 3 | 6 . . |
| . 5 . | . 9 . | . 3 . |
| 4 . . | . . . | . . 8 |
+-------+-------+-------+ Mauricio



Code:
.------------------------.------------------------.------------------------.
| 1       346789  3789   | 578     4578    4579   | 358     5689    2      |
| 6789    2       789    | 1578    3       579    | 158     4       1569   |
| 389     3489    5      | 2       148     6      | 7       189     139    |
:------------------------+------------------------+------------------------:
| 257     17      4      | 3       257     8      | 9       1567    1567   |
| 235789  13789   23789  | 57      6       2457   | 13458   1578    13457  |
| 3578    378     6      | 9       457     1      | 2       578     3457   |
:------------------------+------------------------+------------------------:
| 2789    789     1      | 4       2578    3      | 6       2579    579    |
| 2678    5       278    | 1678    9       27     | 14      3       147    |
| 4       3679    2379   | 1567    1257    257    | 15      12579   8      |
'------------------------'------------------------'------------------------'


ignoring the su de coq...

1. loop... (8)r8c4 = (8-5)r7c5 = (5)r9c456 - (5=1)r9c7 - (1)r9c45 = (1)r8c4; means that r7c5 <> 2,7

2. (1=5)r9c7 - (5)r9c456 = (5-8)r7c5 = (8-6)r8c4 = (6)r9c4; r9c4 <> 1

3. (1=5)r9c7 - (5)r9c456 = (5-8)r7c5 = (8-1)r8c4 = (1)r2c4; r2c7 <> 1

4. (6)r9c4 = (6-8)r8c4 = (8-5)r7c5 = (5)r9c456 - (5=1)r9c7 - (1)r9c5 = (1)r8c4; r8c4 <> 6
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Wed Nov 05, 2008 1:49 am    Post subject: Reply with quote

storm_norm wrote:
ignoring the su de coq...

1. loop... (8)r8c4 = (8-5)r7c5 = (5)r9c456 - (5=1)r9c7 - (1)r9c45 = (1)r8c4; means that r7c5 <> 2,7

Norm, this is a continuous loop and has more eliminations than you indicated.

Code:
 [r7c5]<>27, [r8c4]<>67, [r9c8]<>15

How do these eliminations compare to the Sue de Coq you were trying to avoid?

[Edit: corrected a typo in the cells listed for eliminations.]


Last edited by daj95376 on Wed Nov 05, 2008 11:02 pm; edited 2 times in total
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storm_norm



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Posts: 1741

PostPosted: Wed Nov 05, 2008 2:20 am    Post subject: Reply with quote

ok, yeah, you are right. it does have more eliminations
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ravel



Joined: 21 Apr 2006
Posts: 536

PostPosted: Wed Nov 05, 2008 9:27 am    Post subject: Reply with quote

daj95376 wrote:
How do these eliminations compare to the Sue de Coq you were trying to avoid?

Very interesting loop near the Sue de Coq cells, where 2 cells are revisited.

However the Sue de Coq eliminations are more effective here.

And after this training its much easier to find Smile
I dare say now , that such 4/5-cell Sue de Coq's with a bivalue cell in the row/column aren't much harder to spot than an empty rectangle.
Code:
.------------------------.------------------------.------------------------.
| 1       346789  3789   | 578     4578    4579   | 358     5689    2      |
| 6789    2       789    | 1578    3       579    | 158     4       1569   |
| 389     3489    5      | 2       148     6      | 7       189     139    |
:------------------------+------------------------+------------------------:
| 257     17      4      | 3       257     8      | 9       1567    1567   |
| 235789  13789   23789  | 57      6       2457   | 13458   1578    13457  |
| 3578    378     6      | 9       457     1      | 2       578     3457   |
:------------------------+------------------------+------------------------:
| 2789    789     1      | 4       58-27   3      | 6       2579    579    |
| 2678    5       278    | 168-7   9      @27     | 14      3       147    |
| 4       3679    2379   | 6-157  @15+27  @5+27   |#15      279-15  8      |
'------------------------'------------------------'------------------------'
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Wed Nov 05, 2008 5:27 pm    Post subject: Reply with quote

ravel wrote:
However the Sue de Coq eliminations are more effective here.

Effective is a rather strong term! The SdC only performs more initial eliminations than Norm's continuous loop. In this puzzle, both the SdC and the continuous loop reduce the puzzle to the same grid using Singles.

Code:
 *-----------------------------------------------------------------------------*
 | 1       6       3789    | 578     4578    4579    | 358     589     2       |
 | 789     2       789     | 1578    3       579     | 158     4       6       |
 | 389     4       5       | 2       18      6       | 7       189     139     |
 |-------------------------+-------------------------+-------------------------|
 | 257     17      4       | 3       257     8       | 9       6       157     |
 | 235789  13789   23789   | 57      6       2457    | 13458   1578    13457   |
 | 3578    378     6       | 9       457     1       | 2       578     3457    |
 |-------------------------+-------------------------+-------------------------|
 | 2789    789     1       | 4       58      3       | 6       2579    579     |
 | 6       5       278     | 18      9       27      | 14      3       147     |
 | 4       379     2379    | 6       1257    257     | 15      279     8       |
 *-----------------------------------------------------------------------------*
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ravel



Joined: 21 Apr 2006
Posts: 536

PostPosted: Wed Nov 05, 2008 7:42 pm    Post subject: Reply with quote

daj95376 wrote:
Effective is a rather strong term! The SdC only performs more initial eliminations than Norm's continuous loop. In this puzzle, both the SdC and the continuous loop reduce the puzzle to the same grid using Singles
Ah, thats right. I did not follow the puzzle with all eliminations of the loop, only looked at Norm's solution.
btw for me both need a skyscraper later and it should be r9c8<>15.
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