The New Sudoku Players' Forum

[tarek]

Code: Select all

+-------+-------+-------+
| . 7 . | 3 . 6 | . 9 4 |
| 9 . . | 4 . . | . . 3 |
| . . . | . 7 . | . . . |
+-------+-------+-------+
| 1 2 . | . . 4 | . . 5 |
| . . 7 | . . . | . 2 . |
| 8 . . | 5 . . | . . . |
+-------+-------+-------+
| . . . | . . . | . 6 . |
| 3 . . | . 4 . | 1 . 2 |
| 2 8 . | 9 . . | . 5 . |
+-------+-------+-------+
.7.3.6.949..4....3....7....12...4..5..7....2.8..5............6.3...4.1.228.9...5.


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[Leren]

Code: Select all

*------------------------------------------*
| 5 7   8   | 3    1      6    | 2   9  4  |
| 9 1   2   | 4    58     58   | 6   7  3  |
| 6 3   4   | 2    7      9    | 5   1  8  |
|-----------+------------------+-----------|
| 1 2  b69  |b678 b689    4    | 789 3  5  |
| 4 5   7   |c168  689-3 c138  | 89  2 c16 |
| 8 69  3   | 5    269    127  | 79  4  16 |
|-----------+------------------+-----------|
| 7 4   15  | 18   258    1258 | 3   6  9  |
| 3 69  569 |a67   4      57   | 1   8  2  |
| 2 8   16  | 9   a36     1-3  | 4   5  7  |
*------------------------------------------*

(3=7) r8c4, r9c5 - (7=8) r4c345 - (8=3) r5c469 => - 3 r5c5, r9c6; stte

Leren

[Mauriès Robert]

Hi tarek,
What you do, giving a puzzle every day is very good and I congratulate you.
Nevertheless, I find that these puzzles are easy when it only has one step to solve (so with a backdoor) and are of little interest to me, unless the goal is to show all kinds of patterns.
Some more complicated puzzles will be welcome to my taste.

Here's my resolution with an anti-track (see puzzle)
P'(8r5c46) : [-8r5c46->16r5c49]->3r5c6->3r9c5->6r8c4->[7r4c4 and (9r8c2->9r4c3)]->8r4c7 => -8r5c7, stte.

puzzle: Show

Sincerely
Robert

[Cenoman]

Code: Select all

 +------------------+----------------------+------------------+
 |  5    7    8     |  3     1      6      |  2     9    4    |
 |  9    1    2     |  4     58     58     |  6     7    3    |
 |  6    3    4     |  2     7      9      |  5     1    8    |
 +------------------+----------------------+------------------+
 |  1    2    69    | c678   689    4      | b789   3    5    |
 |  4    5    7     |  168  a689-3  138    | b89    2    16   |
 |  8    69   3     |  5     269    127    |  79    4    16   |
 +------------------+----------------------+------------------+
 |  7    4    15    |  18    258    1258   |  3     6    9    |
 |  3    69   569   | d67    4      57     |  1     8    2    |
 |  2    8    16    |  9    d36     13     |  4     5    7    |
 +------------------+----------------------+------------------+

(9)r5c5 = (98-7)r45c7 = r4c4 - (7=63)b8p48 => -3 r5c5; ste

[yzfwsf]

Code: Select all

.---------------------------------.---------------------------------.---------------------------------.
|  5          7          8        |  3          1          6        |  2          9          4        |
|  9          1          2        |  4          58         58       |  6          7          3        |
|  6          3          4        |  2          7          9        |  5          1          8        |
:---------------------------------+---------------------------------+---------------------------------:
|  1          2          69       |  678        689        4        |  789        3          5        |
|  4          5          7        |  168        3689       138      |  89         2          16       |
|  8          69         3        |  5          269        127      |  79         4          16       |
:---------------------------------+---------------------------------+---------------------------------:
|  7          4          15       |  18         258        1258     |  3          6          9        |
|  3          69         569      |  67         4          57       |  1          8          2        |
|  2          8          16       |  9          36         13       |  4          5          7        |
'---------------------------------'---------------------------------'---------------------------------'

3r5c6=(3-9)r5c5=r5c7-(9=7)r6c7-r6c6=r8c6-(7=6)r8c4-(6=3)r9c5-(3=1)r9c6 => r9c6<>3,r5c6<>1

[Cenoman]

Hi tarek,
What you do, giving a puzzle every day is very good and I congratulate you.
Nevertheless, I find that these puzzles are easy when it only has one step to solve (so with a backdoor) and are of little interest to me, unless the goal is to show all kinds of patterns.
Some more complicated puzzles will be welcome to my taste.

Hi Robert,
The convention of these daily puzzles, convention between the puzzle maker and the puzzle players, is as follows:
- the proposed puzzle is solvable in one "tough" step, with "stte" finish, stte = singles to the end. The tough step is a bit thougher than an X-wing, a swordfish, even finned (and maybe more, I'm not aware of the exact filtering criteria).
- players solve the puzzle from its status after processing basics (i.e. comprehensively lcls techniques, lcls = locked candidates, locked sets, including pointing and box-line interaction).
- each new solution is different from those already posted in the forum. How much different, is left to the player appreciation.
- a common practise is to accompany the solution with a grid of PMs (PM = pencilmarks), in which the nodes of the solution are marked with letters and possibly other symbols.

Your own higher rate puzzles, posted from time to time are welcome, but personally, I am not ready to solve a puzzle rated SE 9.0 everyday (too much time consuming). Some call these "puzzles for masochists !"
You are not the first who thinks, that people who try to find a different ste one-stepper of an easy puzzle are losing their time. Free translation of French expression: if you don't like it, please don't turn others against it!

[eleven]

Agreed.

For solvers, who - with the help of a more or less simple solver - try to find a short or interesting solution, hard puzzles, which need more than one or two steps are very time consumimg, and cannot be done everyday.

Of course programs can do it quickly, but who is interested to read the daily outputs of programs without having tried to find an own solution ? (Chess players are not interested in observing the games of chess computer tournaments too.)

There are very good free programs, which can solve hard puzzles. And also some users have programs, which could output good, but mostly boring solutions to boring hard puzzles. No one seems to be interested in that here.
There was a site, where harder sudokus were discussed, but i cannot find it now.

[Mauriès Robert]

Hi Cenoman and Eleven,
Ok,I understand your points of view and therefore the choice of puzzles that is made here.
Robert

[tarek]

Hi tarek,
What you do, giving a puzzle every day is very good and I congratulate you.
Nevertheless, I find that these puzzles are easy when it only has one step to solve (so with a backdoor) and are of little interest to me, unless the goal is to show all kinds of patterns.
Some more complicated puzzles will be welcome to my taste.

Thanks Robert for your feedback. As the baton was only passed on to me recently, I was going with both consensus & what has already been established here. I see the others have clarified a few of those issues already.

To give everybody an insight of the longlisting process of these puzzles, i'm using Sukaku explainer to filter the puzzles out. The puzzles are all singles backdoor size 1 and at the moment would have an SE rating of less than 8 and would range in difficulty from Uniquenss to forcing chains. This difficulty is based on an electronic solver solving systemically using rules that increase in difficulty. The desire to solve using a single advanced technique is down to the player. I still manually check every puzzle I post to check the likelihood of achieving that. If I think The likelihood of a single step solution is remote then I would discard the puzzle