tough sudoku collection

Post puzzles for others to solve here.

Re: tough sudoku collection

Postby docjohn » Sun Apr 22, 2018 3:15 pm

David P Bird wrote:docjohn,
Congratulations on your efforts. However, to pick up on one point in your definitions; what you call a strong link is actually a conjugate link. With a strong link it is possible for both the linked terms to be true. I haven't checked if this affects any of your other tutorial pages though. See the <AIC Primer Thread>

David PB
.


Thanks Dave. I haven't heard of a conjugate link before. Hopefully I'll learn something here. Thanks for the feedback
docjohn
 
Posts: 24
Joined: 07 January 2011

Re: tough sudoku collection

Postby docjohn » Sun Apr 22, 2018 5:38 pm

But I don't understand why docJohn says it's unsolvable. I thought I showed a solution and that others confirmed the solution.


Marty, I stand corrected. It is indeed a solvable puzzle. My solver (Jet Sudoku) was using a unique rectangle technique incorrectly and creating a false dead end.
Looks like I have some debugging to do.
docjohn
 
Posts: 24
Joined: 07 January 2011

Re: tough sudoku collection # 2

Postby Ngisa » Sun Apr 22, 2018 6:00 pm

Code: Select all
+-----------------+--------------------+------------------------+
| 6     9      8  | 5      7       4   | 1        2       3     |
| 7     2      4  | 19     389     139 | 569      69      5689  |
| 1     3      5  | 6     b89      2   | 7        4      a89    |
+-----------------+--------------------+------------------------+
| 9     7      1  | 3      2       56  | 56       8       4     |
| 8     5      26 | 4     c69      7   | 3        1      f269   |
| 3     4      26 | 8      1      d569 |e2569    e679    e25679 |
+-----------------+--------------------+------------------------+
| 4     16     3  | 19     5       8   | 269      679     2679  |
| 2     8      9  | 7      36      36  | 4        5       1     |
| 5     16     7  | 2      4       19  | 8        3       6-9   |
+-----------------+--------------------+------------------------+

(9=8)r3c9 - (8=9)r3c5 - r5c5 = r6c6 - r6c789 = (9)r5c9 => - 9r9c9; stte

Clement
Ngisa
 
Posts: 783
Joined: 18 November 2012

Previous

Return to Puzzles