The New Sudoku Players' Forum

[AMcK]

This seems to be the most complex Poppacom puzzle yet.

Code: Select all

. 5 . ¦ . . . ¦ . 1 .
4 . . ¦ . . . ¦ . . 8
. 6 3 ¦ 8 . 9 ¦ 7 5 .
------+-------+-------
. . 2 ¦ 3 . 5 ¦ 6 . .
. . . ¦ . . . ¦ . . .
. . 5 ¦ 9 . 2 ¦ 8 . .
------+-------+-------
. 9 1 ¦ 6 . 7 ¦ 5 3 .
3 . . ¦ . . . ¦ . . 7
. 7 . ¦ . . . ¦ . 6 .

Normal rules stall at the following point

Code: Select all

789    5      789    ¦ 247    2347   34     ¦ 2349   1      6     
4      12     79     ¦ 1257   123567 136    ¦ 239    29     8     
12     6      3      ¦ 8      124    9      ¦ 7      5      24     
---------------------+----------------------+----------------------
179    8      2      ¦ 3      147    5      ¦ 6      479    19     
1679   3      479    ¦ 147    14678  1468   ¦ 129    2479   5     
167    14     5      ¦ 9      1467   2      ¦ 8      47     3     
---------------------+----------------------+----------------------
28     9      1      ¦ 6      248    7      ¦ 5      3      24     
3      24     6      ¦ 1245   12459  14     ¦ 1249   8      7     
5      7      48     ¦ 124    123489 1348   ¦ 1249   6      19     


There are no x-wings, unlike previous Sunday puzzles.

My logic solver was able to complete the puzzle with 25 contradictions, 10 verities and 3 veracities. I am advised that two of the contradiction cycles are sufficient to break the puzzle and there is a "turbot" classification of them. This is certainly the toughest newspaper puzzle I have yet seen.

How far will Poppacom push the Sunday Times Superior Version?
Regards
Andrew

[Bigtone53]

From memory, there is a hidden quad in column 5 which leads to a placement in row 2. 2 straightforward x-wings and you're done. I would have to do it again to recall exactly what I did though.

[emm]

Xwing 4s = r37c59

[tarek]

assuming you ignored the naked double in column 9, the x-wing's maximal killing force goes like this..

Code: Select all

*--------------------------------------------------------------------------*
| 2789    5       789    | 247    -2347    34     | 2349    1       6      |
| 4       12      79     | 1257    123567  136    | 239     29      8      |
| 12      6       3      | 8      *124     9      | 7       5      *24     |
|------------------------+------------------------+------------------------|
| 179     8       2      | 3      -147     5      | 6       479     19     |
| 1679    3       479    | 147    -14678   1468   | 129     2479    5      |
| 167     14      5      | 9      -1467    2      | 8       47      3      |
|------------------------+------------------------+------------------------|
| 28      9       1      | 6      *248     7      | 5       3      *24     |
| 3       24      6      | 1245   -12459   14     | 1249    8       7      |
| 5       7       48     | 124    -123489  1348   | 1249    6      -1249   |
*--------------------------------------------------------------------------*
Eliminating 4 From r1c5 ( XWing in Rows 37)
Eliminating 4 From r4c5 ( XWing in Rows 37)
Eliminating 4 From r5c5 ( XWing in Rows 37)
Eliminating 4 From r6c5 ( XWing in Rows 37)
Eliminating 4 From r8c5 ( XWing in Rows 37)
Eliminating 4 From r9c5 ( XWing in Rows 37)
Eliminating 4 From r9c9 ( XWing in Rows 37)

solving the puzzle,

Spotting the naked double in column 9, or the double in box 1 (which allows you to construct another x-wing in 2s) would still leave you in need of the mentioned x-wing but with less eliminations....

Tarek

[MCC]

After the x-wing eliminations in 4's you'll find that the 4's in box 5 are locked in row 5 allowing you to eliminate the 4's in r5c3 and r5c8 and place some numbers.

MCC