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Skyscraper

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Skyscraper

Postby strmckr on Sun May 10, 2009 3:00 am

A skyscraper is essentially

A Sashimi x-wing in two directions.

Code: Select all

/  /  N | / / / | / / N
.  x  . | . . . | . . .
.  x  . | . . . | . . .
--------+-------+-------
/  N  / | / / / | / / N
.  .  x | . . . | . . .
.  .  x | . . . | . . .
--------+-------+-------
.  .  . | . . . | . . .
.  .  . | . . . | . . .
.  .  . | . . . | . . .


KEY: '/' <=> cells void of candidate 'N'
'N' <=> cells with candidate 'N'; all are required
"-X" <=> potential eliminations of candidate 'N'


the pattern is a 2 points on columns that are weakly linked and strongly linked between rows .
where placement of N at any point eliminates x.
Last edited by strmckr on Fri Jul 10, 2009 4:13 pm, edited 7 times in total.
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Re: Skyscraper

Postby strmckr on Sun May 10, 2009 3:02 am

example on rows:
Code: Select all
.---------------.------------.----------------.
| 4   1     5   | 7    39  2 | 8    369  36   |
| 9-2  2369  369 | 8    1   4 | 279  5    237 |
| 7   239@   8   | 5    39  6 | 1    239@  4  |
:---------------+------------+----------------:
| 1   8     2   | 6    4   3 | 5    7    9    |
| 5   39    39  | 1    8   7 | 26   4    26   |
| 6   4     7   | 2    5   9 | 3    8    1    |
:---------------+------------+----------------:
| 29@  7     1   | 39   6   5 | 4    239@  8  |
| 8   569   469 | 349  2   1 | 679  369  3567 |
| 3   569-2  469 | 49   7   8 | 269  1   256  |
'---------------'------------'----------------'


2 in r3c2,r7c1 (connected by r37c8) => r2c1,r9c2<>2

and
example on columns:
Code: Select all
.---------------.------------.----------------.
| 4   1     5   | 7    39  2 | 8    369  36   |
| 29@  2369  369 | 8    1   4 | 79-2  5   37-2|
| 7   39-2   8   | 5    39  6 | 1    239@  4  |
:---------------+------------+----------------:
| 1   8     2   | 6    4   3 | 5    7    9    |
| 5   39    39  | 1    8   7 | 26   4    26   |
| 6   4     7   | 2    5   9 | 3    8    1    |
:---------------+------------+----------------:
| 29@  7     1   | 39   6   5 | 4    239@  8  |
| 8   569   469 | 349  2   1 | 679  369  3567 |
| 3   2569  469 | 49   7   8 | 269  1    256  |
'---------------'------------'----------------'


2 in r2c1,r3c8 (connected by r7c18) => r2c79,r3c2<>2
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Re: Skyscraper

Postby lancehoch on Sun May 10, 2009 4:06 pm

I think there are extra symbols in your code in the first post. Where does the X come into play?
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Re: Skyscraper

Postby strmckr on Sun May 10, 2009 5:32 pm

more typos.. i need to proof read more befor i copy it ever where.

the x's are eliminations of digit N.
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