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Postby ArkieTech » Thu Dec 14, 2006 1:59 pm


Carcul wrote:
That is part of the riddle. However, I can say that there are two simple steps in front of your eyes which, in the right order, solve the puzzle.
Ravel Responded:
Sorry Carcul, but ArkieTech wrote "I am just learning ", so we dont know, if he is familiar with unique rectangles and BUG (or whatever steps you mean).



I know what Unique rectangles and BUGs are. Being familiar enough to spot them is my problem.

I am studying the riddle. With new knowledge that:

1. the order of the needed steps is important.
2. and/or "solving the puzzle" can mean more than just singles and simple stuff left to complete the puzzle.

Thanks

dan
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Postby Carcul » Thu Dec 14, 2006 2:49 pm

ArkieTech wrote:I know what Unique rectangles and BUGs are.


BUGs are not needed here. Uniqueness is enough.

ArkieTech wrote:I am studying the riddle.


Note that the "and the puzzle is solved" part of the riddle is the easy one.

Carcul
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fully symmetric

Postby claudiarabia » Thu Dec 14, 2006 2:49 pm

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


1 swordfish, 2xy, 1UR type 4

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Postby Carcul » Thu Dec 14, 2006 2:57 pm

Claudiarabia wrote:1 swordfish, 2xy, 1UR type 4


The type-1 AUR is enough: [r4c8]=8|3=[r4c5]-3-[r4c7](-6-[r4c8])-6-
-[r6c8]-4-[r4c8], => r4c8<>4,6 => r4c8=8.

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Postby ArkieTech » Thu Dec 14, 2006 3:22 pm

Code: Select all
 *--------------------------------------------------*
 | 12   8    12   | 46   7    34   | 56   356  9    |
 | 4    3    6    | 5    1    9    | 78   2    78   |
 | 7    9    5    | 2    68   38   | 4    36   1    |
 |----------------+----------------+----------------|
 | 235  1    237  | 8    4    6    | 57   9    27   |
 | 58   4    9    | 17   2    17   | 3    58   6    |
 | 28   6    27   | 3    9    5    | 1    4    278  |
 |----------------+----------------+----------------|
 | 6    2    8    | 47   3    47   | 9    1    5    |
 | 13   5    134  | 9    68   2    | 68   7    34   |
 | 9    7    34   | 16   5    18   | 2    68   34   |
 *--------------------------------------------------*


r3c5 at either 8 or 6 r3c8 has to be a 3

Isn't that unique:D

Thanks Carcul

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Postby ravel » Thu Dec 14, 2006 3:35 pm

ArkieTech wrote:r3c5 at either 8 or 6 r3c8 has to be a 3
Oops, the name for this is "remote pairs" (but i saw the UR first, which leads to a BUG+1).
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Postby Carcul » Thu Dec 14, 2006 5:09 pm

Ravel wrote:Oops, the name for this is "remote pairs"


Or colors. Alternatively, we could use an ATILA to conclude that r1c8=6.

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xy-wing

Postby claudiarabia » Fri Dec 15, 2006 11:44 am

ArkieTech wrote:
Code: Select all
 *--------------------------------------------------*
 | 12   8    12   | 46   7    34   | 56   356  9    |
 | 4    3    6    | 5    1    9    | 78   2    78   |
 | 7    9    5    | 2    68   38   | 4    36   1    |
 |----------------+----------------+----------------|
 | 235  1    237  | 8    4    6    | 57   9    27   |
 | 58   4    9    | 17   2    17   | 3    58   6    |
 | 28   6    27   | 3    9    5    | 1    4    278  |
 |----------------+----------------+----------------|
 | 6    2    8    | 47   3    47   | 9    1    5    |
 | 13   5    134  | 9    68   2    | 68   7    34   |
 | 9    7    34   | 16   5    18   | 2    68   34   |
 *--------------------------------------------------*

dan


I found an xy-wing in r3c8 as center and r3c6 and r9c8 as wings. The 8 in r9c6 will be removed. The rest is easy.
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Postby ArkieTech » Fri Dec 15, 2006 12:52 pm

claudiarabia said:

Code: Select all
 *--------------------------------------------------*
 | 12   8    12   | 46   7    34   | 56   356  9    |
 | 4    3    6    | 5    1    9    | 78   2    78   |
 | 7    9    5    | 2    68   38   | 4    36   1    |
 |----------------+----------------+----------------|
 | 235  1    237  | 8    4    6    | 57   9    27   |
 | 58   4    9    | 17   2    17   | 3    58   6    |
 | 28   6    27   | 3    9    5    | 1    4    278  |
 |----------------+----------------+----------------|
 | 6    2    8    | 47   3    47   | 9    1    5    |
 | 13   5    134  | 9    68   2    | 68   7    34   |
 | 9    7    34   | 16   5    18   | 2    68   34   |
 *--------------------------------------------------*


I found an xy-wing in r3c8 as center and r3c6 and r9c8 as wings. The 8 in r9c6 will be removed. The rest is easy.


Thanks claudiarabia I can't tell you how long I looked at that puzzle without seeing the xy-wing.

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Postby udosuk » Fri Dec 15, 2006 1:07 pm

Code: Select all
 *--------------------------------------------------*
 | 12   8    12   | 46   7    34   | 56   356  9    |
 | 4    3    6    | 5    1    9    | 78   2    78   |
 | 7    9    5    | 2    68   38   | 4    36   1    |
 |----------------+----------------+----------------|
 | 235  1    237  | 8    4    6    | 57   9    27   |
 | 58   4    9    | 17   2    17   | 3    58   6    |
 | 28   6    27   | 3    9    5    | 1    4    278  |
 |----------------+----------------+----------------|
 | 6    2    8    | 47   3    47   | 9    1    5    |
 | 13   5   #134  | 9    68   2    | 68   7   *34   |
 | 9    7   *34   | 16   5    18   | 2    68  *34   |
 *--------------------------------------------------*

The simplest uniqueness move I see is the UR (type 1) in r89c39 -> r8c3=1
However it doesn't solve the puzzle and you'll need some extra advanced moves to finish the job, such as ravel's BUG+1, Dan's remote pair, Carcul's ATILA or Claudia's XY-Wing... Simple Sudoku uses a simple coloring move to solve it...
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Postby wapati » Sat Dec 16, 2006 6:10 am

Brutal.

Code: Select all
. . 8|. 5 .|7 . .
. . .|2 . 9|5 . .
5 . .|8 . .|. 9 6
-----+-----+-----
. 7 9|. 2 .|. 5 .
3 . .|5 . 8|. . 2
. 2 .|. 1 .|4 3 .
-----+-----+-----
9 8 .|. . 4|. . 5
. . 6|1 . 5|. . .
. . 7|. 8 .|3 . .
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Postby Carcul » Sat Dec 16, 2006 11:34 am

Udosuk wrote:The simplest uniqueness move I see is the UR (type 1) in r89c39 -> r8c3=1. However it doesn't solve the puzzle


Look closer.

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Postby udosuk » Sun Dec 17, 2006 1:07 am

Carcul wrote:Look closer.

I did notice another UR (don't know its type):
Code: Select all
 *--------------------------------------------------*
 | 12   8    12   | 46   7    34   | 56   356  9    |
 | 4    3    6    | 5    1    9    | 78   2    78   |
 | 7    9    5    | 2    68   38   | 4    36   1    |
 |----------------+----------------+----------------|
 | 235  1   *237  | 8    4    6    | 57   9   *27   |
 | 58   4    9    | 17   2    17   | 3    58   6    |
 | 28   6   *27   | 3    9    5    | 1    4   *278  |
 |----------------+----------------+----------------|
 | 6    2    8    | 47   3    47   | 9    1    5    |
 | 13   5    134  | 9    68   2    | 68   7    34   |
 | 9    7    34   | 16   5    18   | 2    68   34   |
 *--------------------------------------------------*

Which enables me to deduce r4c3<>2 and r6c9<>7
However that doesn't make a difference...:(

After the UR type 1 this state is reached:
Code: Select all
 *--------------------------------------------------*
 | 1    8    2    | 46   7    34   | 56   356  9    |
 | 4    3    6    | 5    1    9    | 78   2    78   |
 | 7    9    5    | 2    68   38   | 4    36   1    |
 |----------------+----------------+----------------|
 | 25   1    3    | 8    4    6    | 57   9    27   |
 | 58   4    9    | 17   2    17   | 3    58   6    |
 | 28   6    7    | 3    9    5    | 1    4    28   |
 |----------------+----------------+----------------|
 | 6    2    8    | 47   3    47   | 9    1    5    |
 | 3    5    1    | 9    68   2    | 68   7    4    |
 | 9    7    4    | 16   5    18   | 2    68   3    |
 *--------------------------------------------------*

Beside the obvious BUG+1 in r1c8 or a simple colors/turbot fish on 6 or the xy-wing in r39c68 or the remote pair of {68} in c5+b9, I can't find any BASIC move to make progress...

Please give more helpful advices other than "look closer"...:(
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Postby wapati » Sun Dec 17, 2006 5:38 am

Nasty puzzle.

Code: Select all
. . . | . 5 . | 9 . .
. . 2 | 4 . . | . 1 8
. 7 . | . 9 . | . 2 .
---------------------
. 5 . | . 6 . | . . .
9 . 7 | 5 . . | . . 1
. . . | . . 7 | 4 8 .
---------------------
2 . . | . . 5 | . 7 .
. 1 9 | . . 6 | 8 . .
. 3 . | . 8 . | . . .
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Postby Carcul » Sun Dec 17, 2006 12:12 pm

Udosuk wrote:I did notice another UR (don't know its type):


Type-2 AUR.

Udosuk wrote:Which enables me to deduce r4c3<>2 and r6c9<>7


The AUR enables you to deduce r4c3<>2,7 => r4c3=3.

Udosuk wrote:I can't find any BASIC move to make progress...


I said that the two moves were SIMPLE, not BASIC. There is a difference.

Udosuk wrote:Please give more helpful advices other than "look closer"...


Look even closer.:D

Carcul
Last edited by Carcul on Sun Dec 17, 2006 8:27 am, edited 1 time in total.
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