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by **jaycarr** » Tue Mar 07, 2006 5:16 pm

[code]
8| 2| 14| 6| 3| 9| 5| 7| 14
---+---+---+---+---+---+---+----+----
34| 6| 5|128| 12| 7|134|1348| 9
---+---+---+---+---+---+---+----+----
9| 7| 13| 18| 5| 4| 2| 138| 6
---+---+---+---+---+---+---+----+----
1| 9| 24| 3| 24| 8| 7| 6| 5
---+---+---+---+---+---+---+----+----
346| 48| 68| 7| 9| 5|134| 134| 2
---+---+---+---+---+---+---+----+----
7| 5|234| 12|124| 6| 34| 9| 8
---+---+---+---+---+---+---+----+----
2| 13| 9| 4| 8| 13| 6| 5| 7
---+---+---+---+---+---+---+----+----
5|134| 7| 9| 6| 13| 8| 2| 14
---+---+---+---+---+---+---+----+----
46|148| 68| 5| 7| 2| 9| 14| 3
[/code]

[code]
8| | | | 3| 9| | |
---+---+---+---+---+---+---+----+----
| 6| 5| | | 7| | 8|
---+---+---+---+---+---+---+----+----
| 7| | | | 4| 2| | 6
---+---+---+---+---+---+---+----+----
1| 9| | 3| | | | 6| 5
---+---+---+---+---+---+---+----+----
| | | | | | | |
---+---+---+---+---+---+---+----+----
7| 5| | | | 6| | 9| 8
---+---+---+---+---+---+---+----+----
2| | 9| 4| | | | 5|
---+---+---+---+---+---+---+----+----
| | | 9| | | 8| 2|
---+---+---+---+---+---+---+----+----
| | | 5| 7| | | | 3
[/code]

by **tarek** » Tue Mar 07, 2006 5:27 pm

hi jaycarr,

Fantastic puzzle........

This requires some advanced techniques....

my take on it....

Code: Select all: *--------------------------------------------------------* | 8 2 14 | 6 3 9 | 5 7 14 | |*34 6 5 | 128 12 7 |*134 1348 9 | | 9 7 13 | 18 5 4 | 2 138 6 | |------------------+------------------+------------------| | 1 9 24 | 3 24 8 | 7 6 5 | |*346 48 68 | 7 9 5 |*134 -134 2 | | 7 5 234 | 12 124 6 |#34 9 8 | |------------------+------------------+------------------| | 2 13 9 | 4 8 13 | 6 5 7 | | 5 134 7 | 9 6 13 | 8 2 14 | | 46 148 68 | 5 7 2 | 9 14 3 | *--------------------------------------------------------* Eliminating 3 From r5c8 (Finned XWing in Columns 17)

Then a box-line elimination followed by a naked double....

Code: Select all: *-----------------------------------------------* | 8 2 14 | 6 3 9 | 5 7 14 | | 34 6 5 | 128 12 7 | 14 38 9 | | 9 7 13 | 18 5 4 | 2 38 6 | |---------------+---------------+---------------| | 1 9 24 | 3 24 8 | 7 6 5 | | 346 *48 68 | 7 9 5 | 134 *14 2 | | 7 5 234 | 12 124 6 | 34 9 8 | |---------------+---------------+---------------| | 2 13 9 | 4 8 13 | 6 5 7 | | 5 #134 7 | 9 6 13 | 8 2 14 | |-46 *148 68 | 5 7 2 | 9 *14 3 | *-----------------------------------------------* Eliminating 4 From r9c1 (Finned XWing in Columns 28) then *-----------------------------------------------* | 8 2 14 | 6 3 9 | 5 7 14 | |*34 6 5 | 128 12 7 |*14 38 9 | | 9 7 13 | 18 5 4 | 2 38 6 | |---------------+---------------+---------------| | 1 9 24 | 3 24 8 | 7 6 5 | |*34 8 6 | 7 9 5 |*134 -14 2 | | 7 5 234 | 12 124 6 | 34 9 8 | |---------------+---------------+---------------| | 2 13 9 | 4 8 13 | 6 5 7 | | 5 134 7 | 9 6 13 | 8 2 14 | | 6 14 8 | 5 7 2 | 9 14 3 | *-----------------------------------------------* Eliminating 4 From r5c8 (Finned XWing in Columns 17)

you could do the last step first, but then you'll miss all the fun...... but just in case here is the single step solution.......

Code: Select all: *--------------------------------------------------------* | 8 2 14 | 6 3 9 | 5 7 14 | |*34 6 5 | 128 12 7 |*134 1348 9 | | 9 7 13 | 18 5 4 | 2 138 6 | |------------------+------------------+------------------| | 1 9 24 | 3 24 8 | 7 6 5 | |*346 48 68 | 7 9 5 |*134 -134 2 | | 7 5 234 | 12 124 6 |#34 9 8 | |------------------+------------------+------------------| | 2 13 9 | 4 8 13 | 6 5 7 | | 5 134 7 | 9 6 13 | 8 2 14 | | 46 148 68 | 5 7 2 | 9 14 3 | *--------------------------------------------------------* Eliminating 34 From r5c8 (Finned XWing in Columns 17)

Tarek

by **tso** » Tue Mar 07, 2006 5:41 pm

jaycarr wrote:
Code: Select all
8| 2| 14| 6| 3| 9| 5| 7| 14 ---+---+---+---+---+---+---+----+---- 34| 6| 5|128| 12| 7|134|1348| 9 ---+---+---+---+---+---+---+----+---- 9| 7| 13| 18| 5| 4| 2| 138| 6 ---+---+---+---+---+---+---+----+---- 1| 9| 24| 3| 24| 8| 7| 6| 5 ---+---+---+---+---+---+---+----+---- 346| 48| 68| 7| 9| 5|134| 134| 2 ---+---+---+---+---+---+---+----+---- 7| 5|234| 12|124| 6| 34| 9| 8 ---+---+---+---+---+---+---+----+---- 2| 13| 9| 4| 8| 13| 6| 5| 7 ---+---+---+---+---+---+---+----+---- 5|134| 7| 9| 6| 13| 8| 2| 14 ---+---+---+---+---+---+---+----+---- 46|148| 68| 5| 7| 2| 9| 14| 3

Code: Select all
8| | | | 3| 9| | | ---+---+---+---+---+---+---+----+---- | 6| 5| | | 7| | 8| ---+---+---+---+---+---+---+----+---- | 7| | | | 4| 2| | 6 ---+---+---+---+---+---+---+----+---- 1| 9| | 3| | | | 6| 5 ---+---+---+---+---+---+---+----+---- | | | | | | | | ---+---+---+---+---+---+---+----+---- 7| 5| | | | 6| | 9| 8 ---+---+---+---+---+---+---+----+---- 2| | 9| 4| | | | 5| ---+---+---+---+---+---+---+----+---- | | | 9| | | 8| 2| ---+---+---+---+---+---+---+----+---- | | | 5| 7| | | | 3

Please make sure Disable BBCode in this post is UNCHECKED or your diagram will not appear correctly. Maybe you could copy the way most other people make their grids to make it easier on the rest of us. See this post.

The starting grid you gave has an '8' at r2c8 which makes the puzzle unsolvable. This appears to be a typo as it makes the puzzle asymetrical and you don't have an 8 there in your partially completed grid.

Starting grid:

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

Position now:

Code: Select all: *-----------------------------------------------------------* | 8 2 14 | 6 3 9 | 5 7 14 | | 34 6 5 | 128 12 7 | 134 1348 9 | | 9 7 13 | 18 5 4 | 2 138 6 | |-------------------+-------------------+-------------------| | 1 9 24 | 3 24 8 | 7 6 5 | | 346 48 68 | 7 9 5 | 134 134 2 | | 7 5 234 | 12 124 6 | 34 9 8 | |-------------------+-------------------+-------------------| | 2 13 9 | 4 8 13 | 6 5 7 | | 5 134 7 | 9 6 13 | 8 2 14 | | 46 148 68 | 5 7 2 | 9 14 3 | *-----------------------------------------------------------*

One possible next step is Simple Coloring on3s:

Code: Select all: *-----------------------------------------------------------* | 8 2 14 | 6 3 9 | 5 7 14 | |-34 6 5 | 128 12 7 | 1x34 1348 9 | | 9 7 13 | 18 5 4 | 2 138 6 | |-------------------+-------------------+-------------------| | 1 9 24 | 3 24 8 | 7 6 5 | |+346 48 68 | 7 9 5 | 134 134 2 | | 7 5 2-34 | 12 124 6 |+34 9 8 | |-------------------+-------------------+-------------------| | 2 13 9 | 4 8 13 | 6 5 7 | | 5 134 7 | 9 6 13 | 8 2 14 | | 46 148 68 | 5 7 2 | 9 14 3 | *-----------------------------------------------------------*

Either all the 3s marked with PLUS are 'true' and the 3s marked MINUS are 'false' OR vice versa. Either way, there will be a 3 in the same row or column as r2c7 -- therefore, you can exclude 3 from that cell.

To complete the puzzle, you will probably need Simple Coloring again using a different candidate.

by **CathyW** » Tue Mar 07, 2006 6:39 pm

Uniqueness on r78c2 and r78c6 places 4 at r8c2. The rest is then straightforward.

by **ravel** » Tue Mar 07, 2006 6:58 pm

"Disable BBCode" - ah finally i know how i can write [code][/code] in my posts

by **tso** » Tue Mar 07, 2006 7:55 pm

CathyW wrote:Uniqueness on r78c2 and r78c6 places 4 at r8c2. The rest is then straightforward.

CathyW's solution is *much* simpler than the one I gave using coloring.

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