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VH+081017

 
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immpy



Joined: 06 May 2017
Posts: 570

PostPosted: Thu Aug 10, 2017 8:52 pm    Post subject: VH+081017 Reply with quote

Enjoy the puzzle...

Code:

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

Play this puzzle online at the Daily Sudoku site
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JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium

PostPosted: Thu Aug 10, 2017 10:29 pm    Post subject: Reply with quote

3 singles; exclusions by the solutions of the 4s, C1; 1 single
Code:
+---------------------+-----------------------+-----------------------+
| 13      1378   38   | 5      6      1237    | 4       1237    9     |
| 2       13478  368  | 9      14     137     | 1358    1367    35678 |
| 46      5      9    | 12347  8      1237    | 13      12367   2367  |
+---------------------+-----------------------+-----------------------+
| 8       6      4    | 123    12(5)  123(59) | 7       123(9)  23    |
| 13(59)  123    235  | 6      7      4       | 138(9)  123(9)  238   |
| 139     123    7    | 8      12     1239    | 6       5       4     |
+---------------------+-----------------------+-----------------------+
| 46      9      56   | 147    3      157     | 2       8       567   |
| 3(5)    2348   2358 | 247    24-5   6       | 359     3479    1     |
| 7       234    1    | 24     9      8       | 35      346     356   |
+---------------------+-----------------------+-----------------------+
5r8c1 5r5c1
      9r5c1 9r5c78
            9r4c8  9r4c6
                   5r4c6 5r4c5 -> 5r8c1==5r4c5 => -5r8c5; stte
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Ajò Dimonios



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

PostPosted: Fri Aug 11, 2017 8:23 am    Post subject: Reply with quote

Hi everyone
Code:

+----------------+----------------+----------------+
| 13   1378 38   | 5    6   1237  | 4    1237  9   |
| 2    1347 36   | 9    14  137   | 58   1367  58  |
| 1346 5    9    | 1234 8   1237  | 13   12367 236 |
+----------------+----------------+----------------+
| 8    6    4    | 123  125 12359 | 7    1239  23  |
| 1359 1239 235  | 6    7   4     | 1389 1239  238 |
| 139  1239 7    | 8    12  1239  | 6    5     4   |
+----------------+----------------+----------------+
| 4569 49   56   | 14   3   15    | 2    8     7   |
| 345  2348 2358 | 7    245 6     | 359  349   1   |
| 7    234  1    | 24   9   8     | 35   346   356 |
+----------------+----------------+----------------+

Play this puzzle online at the Daily Sudoku site


[(5-6)R7C3=(6-9)R7C1; (5)R7C3-(5)R5C3=(5-9)R5C1 and (5)R7C3-(5)R7C6=(5-9)R4C6=(9)R6C6-(9)R6C1=>contradiction 0 singles 9 in column 1=>-5R7C3=>stte.

Ciao a Tutti
Paolo
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Ajò Dimonios



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

PostPosted: Fri Aug 11, 2017 8:24 am    Post subject: Reply with quote

Hi everyone
Code:

+----------------+----------------+----------------+
| 13   1378 38   | 5    6   1237  | 4    1237  9   |
| 2    1347 36   | 9    14  137   | 58   1367  58  |
| 1346 5    9    | 1234 8   1237  | 13   12367 236 |
+----------------+----------------+----------------+
| 8    6    4    | 123  125 12359 | 7    1239  23  |
| 1359 1239 235  | 6    7   4     | 1389 1239  238 |
| 139  1239 7    | 8    12  1239  | 6    5     4   |
+----------------+----------------+----------------+
| 4569 49   56   | 14   3   15    | 2    8     7   |
| 345  2348 2358 | 7    245 6     | 359  349   1   |
| 7    234  1    | 24   9   8     | 35   346   356 |
+----------------+----------------+----------------+

Play this puzzle online at the Daily Sudoku site.

Similar solution


[(6)R2C3-(6)R7C3=(6-9)R7C1; (6)R2C3-(6=5)R7C3-(5)R5C3=(5-9)R5C1 and (6)R2C3-(6=5)R7C3-(5)R7C6=(5-9)R4C6=(9)R6C6-(9)R6C1=>contradiction 0 singles 9 in column 1=>-6R2C3=>stte.

Ciao a Tutti
Paolo
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Clement



Joined: 24 Apr 2006
Posts: 1110
Location: Dar es Salaam Tanzania

PostPosted: Fri Aug 11, 2017 5:20 pm    Post subject: VH+801017 Reply with quote

Code:

+-------------------------+------------------------+-----------------------+
|c13       c1378    c38   |  5        6      1237  | 4       1237     9    |
| 2        c1347    c36   |  9       d14     137   | 58      1367     58   |
| 1346      5        9    | e12347    8      1237  | 13      12367    2367 |
+-------------------------+------------------------+-----------------------+
| 8         6        4    |  123      125    12359 | 7       1239     23   |
| 1359      1239     235  |  6        7      4     | 1389    1239     238  |
| 139       1239     7    |  8        12     1239  | 6       5        4    |
+-------------------------+------------------------+-----------------------+
| 4569      9-4     b56   |af147      3     a157   | 2       8       a57   |
| 345       2348     2358 |  27-4     245    6     | 359     3479     1    |
| 7         234      1    |  2-4      9      8     | 35      346      356  |
+-------------------------+------------------------+-----------------------+

(4=175)r7c469 - (5=6)r7c3 - (6=4)r1c123, r2c23 - (4)r2c5 = (4)r3c4 - (4)r7c4 (a loop) => - 4 r7c2, r89c4; stte
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JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium

PostPosted: Sat Aug 12, 2017 10:21 am    Post subject: Re: VH+801017 Reply with quote

Clement wrote:
(4=175)r7c469 - (5=6)r7c3 - (6=4)r1c123, r2c23 - (4)r2c5 = (4)r3c4 - (4)r7c4 (a loop) => - 4 r7c2, r89c4; stte
Hi Clement,

Interesting loop, however

1. your hyper-condensed Eureka notation doesn't allow to simply determine all the exclusions! Instead, it is better to write your loop as the following wisiwig symmetric pigeonhole matrix based on your 10 native SIS/constraints. Because, the 10 columns are native or derived SIS/constraints, it immediately gives 5 exclusions : 4r89c4, 5r7c1, (13)r3c1. Furthermore, it contains 2 exclusion matrices excluding 1r1c6 and 4r7c2.
Code:
+---------------------+----------------------+-------------------+
| (13)   (1378)  (38) | 5        6     237-1 | 4     1237   9    |
| 2      (1347)  (36) | 9        1(4)  137   | 58    1367   58   |
| 46-13  5       9    | 1237(4)  8     1237  | 13    12367  2367 |
+---------------------+----------------------+-------------------+
| 8      6       4    | 123      125   12359 | 7     1239   23   |
| 1359   1239    235  | 6        7     4     | 1389  1239   238  |
| 139    1239    7    | 8        12    1239  | 6     5      4    |
+---------------------+----------------------+-------------------+
| 469-5  9-4     (56) | (147)    3     (157) | 2     8      (57) |
| 345    2348    2358 | 27-4     245   6     | 359   3479   1    |
| 7      234     1    | 2-4      9     8     | 35    346    356  |
+---------------------+----------------------+-------------------+
*4r7c4*| 1r7c4  7r7c4      |
       |&1r7c6& 7r7c6 5r7c6|
       |        7r7c9 5r7c9|
                      5r7c3 6r7c3
                           |6r2c3 3r2c3
                           |      3r1c1 &1r1c1&                    | -> 1r7c6==1r1c1 -> -1r1c6
                           |      3r1c3         8r1c3              |
                           |      3r1c2  1r1c2  8r1c2 7r1c2        |
                           |      3r2c2  1r2c2        7r2c2 *4r2c2*| -> 4r7c4==4r2c2 -> -4r7c2
 4r3c4                                                       4r2c5
 |                    |           |      |
 V                    V           V      V
-4r89c4              -5r7c1      -3r3c1 -1r3c1

2. it doesn't solved the puzzle stte!

JC
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Ajò Dimonios



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

PostPosted: Sat Aug 12, 2017 11:37 am    Post subject: Reply with quote

Hi Clement and JC

The singles after basics are 5 (R4C3=4, R6C4=8, R6C7=6, R7C9=7,R8C4=7).


Ciao a Tutti

Paolo
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JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium

PostPosted: Sat Aug 12, 2017 12:30 pm    Post subject: Reply with quote

Hi Paolo,

In my solution, I optimized the rational basics, otherwise they would lead to 7 singles !

JC
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immpy



Joined: 06 May 2017
Posts: 570

PostPosted: Sat Aug 12, 2017 1:39 pm    Post subject: Reply with quote

Here's hoping that all of you good folks are enjoying the puzzles I have been posting. Thank you for your time and interest. I can't make much sense out of the matrices, because I am not familiar with them. Any puzzle I attempt to solve, I do with pencil and paper. It may take me longer and involve more steps, but that is my way of solving them. I like a puzzle that involves more than one step to reach being solved, but higher skilled solvers can sometimes do these in one step. Kudos to all of you that achieve that goal. This one took me 8 steps.

My path began with the X-Wing on (5) which gave me the single of (7) in r7c9, and made r8c7<>5. A two string kite (4) and multiple XY-Wings, which were interspersed with another X-Wing and a W-Wing, got me to the end.

I apologize for sucking at the eureka notation.

Thanks all......immpy.
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Ajò Dimonios



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

PostPosted: Sat Aug 12, 2017 1:56 pm    Post subject: Reply with quote

Hi JC


Sorry but what I do not understand in your solution because you started out from a matrix where the 7 in R7C9 and 7 in R8C4 (which are definitely basics) have not yet been resolved and you have instead deleted 4 in column 1 with an advanced technique (fin X-wing) with the final entry of 9 in R7C2. On the one hand, you simplified the initial matrix and made it more complicated by another. However singles after basics are 5 become 7 after fin x-wing together with another fin x-wing of 2.

Ciao a Tutti
Paolo
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JC Van Hay



Joined: 13 Jun 2010
Posts: 494
Location: Charleroi, Belgium

PostPosted: Sat Aug 12, 2017 3:05 pm    Post subject: Reply with quote

Hi Paolo, to avoid any confusion, here is my definition of basics :

Basics : application of the Sudoku puzzle "basic" rule : a candidate is (placed/excluded) if it (belongs/doesn't belong) to all the solutions either of a digit or of a unit.

Furthermore, I repeat : in the actual puzzle, I optimized them to the least number of steps before the exclusion of 5r8c5.

JC
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Ajò Dimonios



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

PostPosted: Sat Aug 12, 2017 8:44 pm    Post subject: Reply with quote

Hi JC

I think I agree with you. For this reason I think the intersection technique of a line with a box falls into this category. In cell R7C9 you can delete 5 and 6 for intersection of line 9 with Box 9 and then insert 7 into R7C9 and consequently 7 in R8C4.
I define as basic technique what sudopedia indicates singles, intersections and subsets.
I agree with http://www.sudokuwiki.org/Strategy_Families

Ciao a Tutti

Paolo
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