Got stuck, can someone please help?

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Got stuck, can someone please help?

Postby domz » Sat Sep 16, 2017 4:06 pm

Hi,

I got stuck with this puzzle:
Code: Select all
. . . | 7 . 6 | . 2 .
5 . . | . . 8 | . . 9
. . 7 | . . 2 | . . 3
------+-------+------
. . 8 | 2 . . | . . .
. 4 . | . 1 . | 7 3 .
1 5 . | . . . | 4 . .
------+-------+------
. . 5 | . 7 . | . 9 .
6 1 . | . . . | 8 . .
. . . | 4 8 . | 3 . 6


I made it this far:
Code: Select all
. . . | 7 . 6 | . 2 .
5 2 . | . . 8 | 6 7 9
. 6 7 | . . 2 | . . 3
------+-------+------
. . 8 | 2 . 4 | 9 . .
. 4 6 | . 1 . | 7 3 .
1 5 . | . . 7 | 4 . .
------+-------+------
. . 5 | 6 7 . | 2 9 .
6 1 . | . 2 . | 8 . 7
. . . | 4 8 . | 3 . 6


and with pencilmarks:
Code: Select all
3489  389  13   |  7    3459  6    |  15  2   48
5     2    134  |  13   34    8    |  6   7   9
423   6    7    |  159  459   2    |  15  58  3
----------------+------------------+-------------
37    37   8    |  2    56    4    |  9   16  15
29    4    6    |  589  1     59   |  7   3   258
1     5    29   |  389  369   7    |  4   68  28
----------------+------------------+-------------
348   38   5    |  6    7     13   |  2   9   14
6     1    34   |  59   2     359  |  8   45   7
279   79   29   |  4    8     15   |  3   15  6


I think i already canceled a lot out, but now i'm stuck and just can't see what to do next :(
Also not sure if i made a mistake and that's why i'm stuck?

Would be really great if someone can have a look and give me a hint at what kind of pattern i should look next :)

Much thanks in advance,
Dominik
domz
 
Posts: 3
Joined: 16 September 2017

Re: Got stuck, can someone please help?

Postby Kozo Kataya » Sun Sep 17, 2017 2:26 pm

Hi domz
In your pm, r3c1<> 423 but = 489 (may be a simple mistake).
A simple solution is to set r8c3=4, though need some more steps including XY-chains etc.
Regards
Kozo Kataya
 
Posts: 25
Joined: 06 July 2012

Re: Got stuck, can someone please help?

Postby Leren » Sun Sep 17, 2017 8:46 pm

The puzzle in line format:

...7.6.2.5....8..9..7..2..3..82......4..1.73.15....4....5.7..9.61....8.....48.3.6

Here is your PM with the correct candidates in r3c1. A grouped Skyscraper/finned X wing in 4' in cells abcd removes the 4 from r3c1.

Code: Select all
*-------------------------------------------*
| 3489 389 d134 | 7   3459 6   | 15  2  48  |
| 5    2   d134 | 13  34   8   | 6   7  9   |
| 89-4 6    7   | 159 459  2   | 15 a48 3   |
|---------------+--------------+------------|
| 37   37   8   | 2   56   4   | 9   16 15  |
| 29   4    6   | 589 1    59  | 7   3  258 |
| 1    5    29  | 389 369  7   | 4   68 28  |
|---------------+--------------+------------|
| 348  38   5   | 6   7    13  | 2   9  14  |
| 6    1   c34  | 59  2    359 | 8  b45 7   |
| 279  79   29  | 4   8    15  | 3   15 6   |
*-------------------------------------------*

A simple column X Wing in 4's in the cells marked * removes the 4's from r1c35.

Code: Select all
*--------------------------------------------*
|*3489 389 13-4 | 7   359-4 6   | 15 2  *48  |
| 5    2   134  | 13  34    8   | 6  7   9   |
| 89   6   7    | 159 459   2   | 15 48  3   |
|---------------+---------------+------------|
| 37   37  8    | 2   56    4   | 9  16  15  |
| 29   4   6    | 589 1     59  | 7  3   258 |
| 1    5   29   | 389 369   7   | 4  68  28  |
|---------------+---------------+------------|
|*348  38  5    | 6   7     13  | 2  9  *14  |
| 6    1   34   | 59  2     359 | 8  45  7   |
| 279  79  29   | 4   8     15  | 3  15  6   |
*--------------------------------------------*

An XY chain in cells abcd removes the 8 from r1c2

Code: Select all
*--------------------------------------------*
| 3489  39-8 13  | 7   359  6   | 15 2  a48  |
| 5     2    134 | 13  34   8   | 6  7   9   |
| 89    6    7   | 159 459  2   | 15 48  3   |
|----------------+--------------+------------|
| 37    37   8   | 2   56   4   | 9  16  15  |
| 29    4    6   | 589 1    59  | 7  3   258 |
| 1     5    29  | 389 369  7   | 4  68  28  |
|----------------+--------------+------------|
| 348  d38   5   | 6   7   c13  | 2  9  b14  |
| 6     1    34  | 59  2    359 | 8  45  7   |
| 279   79   29  | 4   8    15  | 3  15  6   |
*--------------------------------------------*

After a naked quad in Row 1 that removes 39 from r1c1 a second XY chain in cells marked abcde removes the 9 from r5c1.

Code: Select all
*-----------------------------------------*
| 48  39  13  | 7   359 6   | 15  2  c48  |
| 5   2   134 | 13  34  8   | 6   7   9   |
|a89  6   7   | 159 459 2   | 15 b48  3   |
|-------------+-------------+-------------|
| 37  37  8   | 2   56  4   | 9   16  15  |
| 2-9 4   6   | 589 1   59  | 7   3   258 |
| 1   5  e29  | 389 369 7   | 4   68 d28  |
|-------------+-------------+-------------|
| 34  8   5   | 6   7   13  | 2   9   14  |
| 6   1   34  | 59  2   359 | 8   45  7   |
| 279 79  29  | 4   8   15  | 3   15  6   |
*-----------------------------------------*

After a pointing pair that removes 9 from r3c4 and naked pair that removes 5 from r3c5 a third XY chain in cells marked acbd removes the 4 from r3c5.

Code: Select all
*--------------------------------------*
| 48 39 13  | 7    359 6   | 15  2  48 |
| 5  2  134 | 13  a34  8   | 6   7  9  |
| 89 6  7   | 15   9-4 2   | 15 d48 3  |
|-----------+--------------+-----------|
| 37 37 8   | 2    56  4   | 9   16 15 |
| 2  4  6   | 589  1   59  | 7   3  58 |
| 1  5  9   | 38  b36  7   | 4  c68 2  |
|-----------+--------------+-----------|
| 34 8  5   | 6    7   13  | 2   9  14 |
| 6  1  34  | 59   2   359 | 8   45 7  |
| 79 79 2   | 4    8   15  | 3   15 6  |
*--------------------------------------*

The puzzle solves in singles from there. Perhaps not the shortest solution but all the moves are simple. That was a long post. Hopefully no typos.

Leren
Leren
 
Posts: 2853
Joined: 03 June 2012

Re: Got stuck, can someone please help?

Postby domz » Sun Sep 24, 2017 6:35 pm

Wow! That's amazing.
Much thanks for this detailed help. Much appreciated!

Also thanks for pointing out the mistake in r3c1, that was luckily just a typo.

Thanks again, think i learned a lot :)
domz
 
Posts: 3
Joined: 16 September 2017

Re: Got stuck, can someone please help?

Postby JC Van Hay » Sun Sep 24, 2017 8:05 pm

From the 2 solutions of C8 + B9 + ... :
4r3c8 -> 1 solution, while 8r3c8 -> 0 solution

The simultaneous building of those 2 implications [RGT technique] yields either the successive removals given by Leren, or the following extracted "brain obtained" short path :
1. Removal of 4r3c1 by the XWing(4C39)
2. Removal of 8r3c8 due to the following implications :
Code: Select all
+-----------------+-----------------+----------------+
| 3489  389  134  | 7    3459   6   | 15  2      48  |
| 5     2    134  | 13   (34)   8   | 6   7      9   |
| (89)  6    7    | 159  59(4)  2   | 15  -8(4)  3   |
+-----------------+-----------------+----------------+
| 37    37   8    | 2    56     4   | 9   16     15  |
| 2(9)  4    6    | 589  1      59  | 7   3      258 |
| 1     5    2(9) | 389  (369)  7   | 4   (68)   28  |
+-----------------+-----------------+----------------+
| 348   38   5    | 6    7      13  | 2   9      14  |
| 6     1    34   | 59   2      359 | 8   45     7   |
| 279   79   29   | 4    8      15  | 3   15     6   |
+-----------------+-----------------+----------------+
+8r3c8 -> -4r3c8, +4r3c5, -4r2c5, +3r2c5; -8r6c8, +6r6c8; -8r3c1, +9r3c1, -9r5c1, +9r6c3; -(369)r6c5!
or written as a forbidding matrix
Code: Select all
8r3c8
4r3c8 4r3c5
      4r2c5 3r2c5
8r6c8             6r6c8
8r3c1                   9r3c1
                        9r5c1 9r6c3
            3r6c5 6r6c5       9r6c5
or written as a Kraken Cell (369)r6c5 -> derived constraint {4r3c8, 8r6c8, 8r3c1} => -8r3c8
||3r6c5-(3=4)r2c5-4r3c5=4r3c8
||6r6c5-(6=8)r6c8
||9r6c5-9r6c3=9r5c1-(9=8)r3c1
JC Van Hay
 
Posts: 692
Joined: 22 May 2010


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