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Free Press Oct 29, 2010

 
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

PostPosted: Sat Nov 06, 2010 1:15 am    Post subject: Free Press Oct 29, 2010 Reply with quote

A different kettle of fish:
Code:
Puzzle: FP102910
+-------+-------+-------+
| . . . | . . 9 | 7 . 1 |
| . 3 . | . . . | . 9 . |
| . . . | 5 . 7 | 3 . . |
+-------+-------+-------+
| 5 2 . | . 1 . | . . 8 |
| . . . | . 6 . | . . . |
| 6 . . | . . . | 9 4 2 |
+-------+-------+-------+
| . . 2 | 8 . 6 | . . . |
| . 9 . | . . . | . 5 . |
| 7 . 4 | 3 . . | . . . |
+-------+-------+-------+

(No pun intended.)

Keith
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Sat Nov 06, 2010 4:46 am    Post subject: Reply with quote

Code:
+----------------+----------------------+------------------+
| 28    46   5   | 26-4   3      9      | 7      268  1    |
| (28)  3    7   | 16-24  (248)  (1248) | (258)  9    56-4 |
| 9     146  16  | 5      28     7      | 3      28   46   |
+----------------+----------------------+------------------+
| 5     2    39  | 49     1      34     | 6      7    8    |
| 4     7    89  | 29     6      28     | (15)   13   35   |
| 6     18   138 | 7      58     358    | 9      4    2    |
+----------------+----------------------+------------------+
| 13    5    2   | 8      79     6      | 4      13   79   |
| 13    9    68  | 124    247    24-1   | 28-1   5    367  |
| 7     68   4   | 3      259    25(1)  | 28(1)  268  69   |
+----------------+----------------------+------------------+


#1... Loop...(5=1)r5c7 - (1)r9c7 = (1)r9c6 - (1=248)r2c156 - [{28}=5]r2c7;
r2c9 <> 4
r1c4 <> 4
r2c4 <> 2,4
r8c67 <> 1

#2... w-wing {2,8}, pincers in r2c1 and r3c8; r2c7 <> 2

#3... xy-wing {2,5,8} r5c6, r6c5, r9c5; r89c6 <> 2
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Marty R.



Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA

PostPosted: Sat Nov 06, 2010 3:09 pm    Post subject: Reply with quote

It was a tough slog and I didn't see Keith's fish.

DP 28 boxes 123; r2c9<>4
M-Wing (28); r2c7<>2
M-Wing (28); r89c6<>2
XY-Chain; r2c46<>2
XY-Chain; r5c4<>2
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keith



Joined: 19 Sep 2005
Posts: 3355
Location: near Detroit, Michigan, USA

PostPosted: Sat Nov 06, 2010 6:09 pm    Post subject: Reply with quote

There is not a fish. I simply meant it is a different proposition than this week's puzzle. After basics:
Code:
+----------------+----------------+----------------+
| 28   46   5    | 246  3    9    | 7    268  1    |
| 28   3    7    | 1246 248  1248 | 258  9    456  |
| 9    146  16   | 5    28   7    | 3    28   46   |
+----------------+----------------+----------------+
| 5    2    39   | 49   1    34   | 6    7    8    |
| 4    7    89   | 29   6    28   | 15   13   35   |
| 6    18   138  | 7    58   358  | 9    4    2    |
+----------------+----------------+----------------+
| 13   5    2    | 8    79   6    | 4    13   79   |
| 13   9    68   | 124  247  124  | 128  5    367  |
| 7    68   4    | 3    259  125  | 128  268  69   |
+----------------+----------------+----------------+
W-wing 28: R2C7 is not 2. Leading to here:
Code:
+-------------+-------------+-------------+
| 28  4   5   | 26  3   9   | 7   268 1   |
| 28  3   7   | 126 4   128 | 58  9   56  |
| 9   16  16  | 5   28  7   | 3   28  4   |
+-------------+-------------+-------------+
| 5   2   39  | 49  1   34  | 6   7   8   |
| 4   7   89  | 29  6   28  | 15  13  35  |
| 6   18  138 | 7   58  358 | 9   4   2   |
+-------------+-------------+-------------+
| 13  5   2   | 8   9   6   | 4   13  7   |
| 13  9   68  | 124 7   124 | 128 5   36  |
| 7   68  4   | 3   25  125 | 12  68  9   |
+-------------+-------------+-------------+
M-wing: If R3C8 is 2, so is R8C7. R3C8 and R9C8 are pincers on 8. R1C8 is not 8.

Also in the above grid is an XY-wing -258 that takes out 2 in R89C6.

That solves the puzzle. Laughing

Keith
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Sun Nov 07, 2010 12:39 am    Post subject: Reply with quote

A reasonable solution is:

Code:
W-Wing:   (2=8)r2c1 - r1c1 = r1c8 - (8=2)r3c8  =>  r2c7<>2

XY-Chain: (6=2)r1c4 - (2=9)r5c4 - (9=8)r5c3 - (8=6)r8c3 - (6=8)r9c2 - (8=6)r9c8  =>  r1c8<>6
____________________________________________________________________________________________

However, the cells of the XY-Chain can be used in an unreasonable single-stepper network:

Code:
               (2)r3c5           = r3c8            - (2)r9c8
              /                                             \
 (64=2)r1c24 - (2=9)r5c4 - (9=8)r5c3 - r8c3 = r9c2 - (8)r9c8 = (6)r9c8  =>  r1c8<>6
 +--------------------------------------------------------------+
 |  28    46    5     |  246   3     9     |  7     268   1     |
 |  28    3     7     |  1246  248   1248  |  258   9     456   |
 |  9     146   16    |  5     28    7     |  3     28    46    |
 |--------------------+--------------------+--------------------|
 |  5     2     39    |  49    1     34    |  6     7     8     |
 |  4     7     89    |  29    6     28    |  15    13    35    |
 |  6     18    138   |  7     58    358   |  9     4     2     |
 |--------------------+--------------------+--------------------|
 |  13    5     2     |  8     79    6     |  4     13    79    |
 |  13    9     68    |  124   247   124   |  128   5     367   |
 |  7     68    4     |  3     259   125   |  128   268   69    |
 +--------------------------------------------------------------+
 # 66 eliminations remain
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tlanglet



Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills

PostPosted: Sun Nov 07, 2010 5:59 pm    Post subject: Reply with quote

Two steps..........

BUG-Lite+3 (168)r389c237 internal SIS r3c2=4,r89c7=2; r9c9<>6=9
(4)r3c2-(4=6)r3c9;
||
(2)r89c7-(2=86)als:r9c28;

(6)r9c8=(6)r9c2-(6=8)r8c3-(8=9)r5c3-(9=2)r5c4-(2=6)r1c4; r1c8<>6

Ted
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