## Stumped and Bewildered

All about puzzles in newspapers, magazines, and books

### Stumped and Bewildered

Alright so i got stuck on this puzzle from Sudoku for Dummies-Puzzle 240: Diabolical. =P

|6**|7**|3**| |8**|5**|1**| |2**|9**|4**|
|48*|48*|5**| |9**|6**|2**| |1**|37*|37*|
|29*|1**|29*| |3**|7**|4**| |8**|6**|5**|

|42*|5**|1**| |6**|8**|9**| |7**|342|32*|
|7**|428|298| |1**|3**|5**| |49*|428|6**|
|89*|3**|6**| |2**|4**|7**| |5**|1**|89*|

|1**|9**|78*| |4**|2**|6**| |3**|5**|78*|
|3**|6**|27*| |5**|1**|8**| |49*|427|279|
|5**|28*|4**| |7**|9**|3**| |6**|28*|1**|
JSC4490

Posts: 1
Joined: 29 May 2006

I'm not very good at colouring, but I believe that'll solve this nicely. I colored the 8s starting in box 6. The only way I could make a valid assumption was if row6col9 were true (8). If it were false, the assumption would be invalid. I'm sorry for the vague explanation, but I believe it works out right.
Hud

Posts: 570
Joined: 29 October 2005

If r6c9=9
Then r6c1=8, r2c2=8, r9c2=2, r9c8=8
Leaves r5 with too many 4s or no place for an 8
So r6c9 must be 8
underquark

Posts: 299
Joined: 06 September 2005

### Re: Stumped and Bewildered

Just out of curiousity - with all the asterisks shown, was this a "normal" 9X9 sudoku or a 27X27 sudoku puzzle?
Cec
Cec

Posts: 1039
Joined: 16 June 2005

### re: Sudoku for Dummies - Puzzle 240

JSC4490 wrote:i got stuck on this puzzle from Sudoku for Dummies - Puzzle 240: Diabolical
Code: Select all
` 6   7   3   | 8   5   1   | 2   9   4     48  48  5   | 9   6   2   | 1   37  37    29  1   29  | 3   7   4   | 8   6   5    -------------+-------------+------------ 42  5   1   | 6   8   9   | 7   342 32    7   428 298 | 1   3   5   | 49  428 6     89  3   6   | 2   4   7   | 5   1   89   -------------+-------------+------------ 1   9   78  | 4   2   6   | 3   5   78    3   6   27  | 5   1   8   | 49  427 279   5   28  4   | 7   9   3   | 6   28  1   `

Cec: this seems to be a standard-size SuDoku,
with the possibilities shown in each cell.

if c1 8 in r6,
then c3 8 in r7,
and c9 has no 8.

Pat

Posts: 3700
Joined: 18 July 2005

### Stumped and Bewilded

Pat wrote:Cec: this seems to be a standard-size SuDoku,
with the possibilities shown in each cell..."

Thanks Pat. I thought it was a standard-size but the asterisks confused me. In hindsight I should have asked JSC4490 to clarify that it was a standard-size. Hopefully this post will be seen by JSC4490 who may wish to read up on how to post puzzles by clicking on HERE. "Coloring" of the 8's is also another way to solve the puzzle as pointed out above by Hud. On my reckoning the two negative 8's in Box 4 of the following grid means the positive 8's are "true" resulting in the exclusion of all negative 8's from cells r2c2, r5c3, r5c8,r6c1, r7c9 and r9c2.
Code: Select all
` 6   7   3   | 8   5   1   | 2   9   4     48+ 48- 5   | 9   6   2   | 1   37  37    29  1   29  | 3   7   4   | 8   6   5    -------------+-------------+------------ 42  5   1   | 6   8   9   | 7   342 32    7   428+298-| 1   3   5   | 49  428- 6    -89  3   6   | 2   4   7   | 5   1  +89   -------------+-------------+------------ 1   9   78+ | 4   2   6   | 3   5   78-  3   6   27  | 5   1   8   | 49  427 279   5   28- 4   | 7   9   3   | 6   28+ 1   `

Cec
Cec

Posts: 1039
Joined: 16 June 2005

The elimination mentioned can be achieved using the Finned X-wing (Sashimi variation, or the Eyless fish as I would like to name it from now on )
Code: Select all
`*-----------------------------------------------*| 6    7    3   | 8    5    1   | 2    9    4   || 48   48   5   | 9    6    2   | 1    37   37  || 29   1    29  | 3    7    4   | 8    6    5   ||---------------+---------------+---------------|| 24   5    1   | 6    8    9   | 7    234  23  || 7    248 *289 | 1    3    5   | 49  *248  6   || 89   3    6   | 2    4    7   | 5    1    89  ||---------------+---------------+---------------|| 1    9   #78  | 4    2    6   | 3    5    78  || 3    6    27  | 5    1    8   | 49   247  279 || 5   -28  *4   | 7    9    3   | 6   *28   1   |*-----------------------------------------------*Eliminating 8 From r9c2 (Eyeless Finned XWing in Columns 38 with 1 fin in Box 7)`

tarek

Posts: 2895
Joined: 05 January 2006

### Stumped and Bewilded

tarek wrote:"... or the Eyless fish as I would like to name it from now on

tarek, If this suggested name is related to a "fish without eyes" the spelling should be "Eyeless fish"

Cec
Cec

Posts: 1039
Joined: 16 June 2005

The fish missed an EYE & I missed an E......Typing mistake....The Eyeless in the code box below is correct....

Thanx Cec

tarek

tarek

Posts: 2895
Joined: 05 January 2006

So, it's official then; this is a "fsh"? What next; a blind deer (no idea)?
underquark

Posts: 299
Joined: 06 September 2005

There is a Headless Finned Fish [The one with no Vertices on the elimination line, another Sashimi variation, not that common though]

tarek

tarek

Posts: 2895
Joined: 05 January 2006

### Another Solution

Almost Locked Sets XZ-rule:

A=[r8c39]: {2,7,9}; B=[r67c9]: {7,8,9}; x=9; z=7.

So, r8c8<>7 and the puzzle is solved.

Carcul
Carcul

Posts: 724
Joined: 04 November 2005