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Nice puzzles by gsf (VH+)

 
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ravel



Joined: 21 Apr 2006
Posts: 536
PostPosted: Sun Apr 20, 2008 7:20 pm    Post subject: Nice puzzles by gsf (VH+) Reply with quote
Code:
 *-----------*
 |.1.|.2.|...|
 |2.3|4.5|...|
 |.9.|.6.|...|
 |---+---+---|
 |.5.|...|.1.|
 |6.7|...|8.9|
 |.2.|...|.6.|
 |---+---+---|
 |...|.9.|.5.|
 |...|8.2|7.6|
 |...|.7.|.4.|
 *-----------* gsf-1
 *-----------*
 |.1.|.7.|...|
 |3.4|5.6|...|
 |.9.|.1.|...|
 |---+---+---|
 |.8.|...|.9.|
 |9.6|...|4.3|
 |.2.|...|.5.|
 |---+---+---|
 |...|.8.|.7.|
 |...|7.4|8.9|
 |...|.6.|.3.|
 *-----------* gsf-2
 *-----------*
 |.4.|.9.|...|
 |3.7|2.8|...|
 |.5.|.1.|...|
 |---+---+---|
 |.2.|...|.6.|
 |9.6|...|5.2|
 |.7.|...|.8.|
 |---+---+---|
 |...|.3.|.4.|
 |...|5.4|8.7|
 |...|.6.|.2.|
 *-----------*gsf-3

[Edit: removed duplicates]

Last edited by ravel on Mon Apr 21, 2008 7:43 am; edited 1 time in total
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
PostPosted: Sun Apr 20, 2008 9:11 pm    Post subject: Reply with quote
Ravel, puzzles 3-4-5 seem to be the same.
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storm_norm



Joined: 18 Oct 2007
Posts: 1741
PostPosted: Sun Apr 20, 2008 10:26 pm    Post subject: Reply with quote
--------
gsf-1

uniqueness tests should prevail

----

gsf-3

didn't find any "advanced" moves but still took more than a few tries to make sure I did it right.

edit: wow, I thought I saw an x-wing in gsf-2 but not now Embarassed

Last edited by storm_norm on Mon Apr 21, 2008 9:06 pm; edited 1 time in total
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Earl



Joined: 30 May 2007
Posts: 677
Location: Victoria, KS
PostPosted: Mon Apr 21, 2008 2:29 am    Post subject: nice Reply with quote
Norm,

I would appreciate the specifics of the uniqueness tests in gsf-1.

Earl
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storm_norm



Joined: 18 Oct 2007
Posts: 1741
PostPosted: Mon Apr 21, 2008 3:15 am    Post subject: Reply with quote
Code:
457#   1      45#    | 379    2      379    | 6      8      345
2      6      3      | 4      8      5      | 9      7      1
457    9      8      | 1      6      37     | 345    2      345
------------------------------------------------------------------
38     5      9      | 67     34     678    | 24     1      247
6      4      7      | 2      5      1      | 8      3      9
38     2      1      | 79     34     789    | 45     6      457
------------------------------------------------------------------
1      7      26     | 36     9      4      | 23     5      8
45#    3      45#    | 8      1      2      | 7      9      6
9      8      26     | 5      7      36     | 1      4      23


Earl,

the type 1 UR is marked above

-----

I was actually shown this unique pattern in a puzzle here in the forum some months ago... I think it was Keith who gave me the link to the thread with the discussion on the different patterns.

Code:
7      1     #45     | 39     2      39     | 6      8     #45
2      6      3      | 4      8      5      | 9      7      1
45#    9      8      | 1      6      7      | 345    2     #3(45)
------------------------------------------------------------------
38     5      9      | 67     34     68     | 24     1      247
6      4      7      | 2      5      1      | 8      3      9
38     2      1      | 79     34     789    | 45     6      457
------------------------------------------------------------------
1      7      26     | 36     9      4      | 23     5      8
45#    3     #45     | 8      1      2      | 7      9      6
9      8      26     | 5      7      36     | 1      4      23


the logic on the {4,5} pairs marked above is that if r3c9 had {4,5} then the puzzle would have two solutions. the same logic as a unique rectangle because you could then xx the 4 and the 5 in r3c9 and you would still get a valid solution. from what I have read in the forums, this is a "unique loop".
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ravel



Joined: 21 Apr 2006
Posts: 536
PostPosted: Mon Apr 21, 2008 7:51 am    Post subject: Reply with quote
Marty R. wrote:
Ravel, puzzles 3-4-5 seem to be the same.
Thanks, Marty, i removed the last two puzzles, which i copied wrong. Unfortunately i cant recover the 2 puzzles, because gsf changed his list (dont know why), so that also the first puzzle here is missing now. One had a nice 8 cell DP ...
storm_norm wrote:
gsf-2...

x-wing was the nail in the coffin.
I had no x-wing, but one other advanced step solved it for me.
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storm_norm



Joined: 18 Oct 2007
Posts: 1741
PostPosted: Mon Apr 21, 2008 9:10 pm    Post subject: Reply with quote
ravel wrote:
Marty R. wrote:
Ravel, puzzles 3-4-5 seem to be the same.
Thanks, Marty, i removed the last two puzzles, which i copied wrong. Unfortunately i cant recover the 2 puzzles, because gsf changed his list (dont know why), so that also the first puzzle here is missing now. One had a nice 8 cell DP ...
storm_norm wrote:
gsf-2...

x-wing was the nail in the coffin.
I had no x-wing, but one other advanced step solved it for me.


ok, two xy-chains on gsf-2
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