Search found 170 matches

by Fred76
Sun 15 Sep, 2019 1:27 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: What is a Sudoku? Report general consultation
Replies: 9
Views: 295

Re: part 4: Views from the WSC Community

About part 4. I like the existence of this part and the way it puts historical perspective to the report. The Simon Prett article is primordial to my eyes, and the questions are still very actual. Even if the question posed was more about classic vs. variant at this time and now it is more about cla...
by Fred76
Sun 15 Sep, 2019 1:01 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: What is a Sudoku? Report general consultation
Replies: 9
Views: 295

Re: Part 3: Principles defining what a Sudoku “looks like” and “solves like”

About part 3 of this report. I think it's the core of this report, it was the probably the hardest part to write and it is very good. I have however question concerning: X. Principle VI gives rise to classic sudoku solving techniques allowing the placement of symbols using the “Rows and Columns” and...
by Fred76
Sun 15 Sep, 2019 12:48 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: What is a Sudoku? Report general consultation
Replies: 9
Views: 295

Re: Part 2: Summary of Definitions & Recommendations

Still in part 2 of the report: I do not consider it a useful exercise to define precisely and absolutely what “looks like” and “solves like” mean. Even if this is something that could be achieved with sufficient precision, I believe that this would come with at least two major disadvantages: namely ...
by Fred76
Sun 15 Sep, 2019 12:27 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: What is a Sudoku? Report general consultation
Replies: 9
Views: 295

Re: Part 2: Summary of Definitions & Recommendations

I have small concerns with formulation of definition 2 and 3 here. I think it is not a good formulation and that it can even be misleading if you don't read the part 3 of this report. Definition 2 (Sudoku Variant). A Sudoku Variant is a puzzle which both looks like, and solves like a classic sudoku....
by Fred76
Sun 15 Sep, 2019 12:03 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: What is a Sudoku? Report general consultation
Replies: 9
Views: 295

Re: Part 1: Introduction

Here are some comments about part 1: Introduction. I like the way puzzles are spread into the 3 categories (A) classic sudoku, (B) sudoku variant and (C) sudoku hybrid. You all know I've some concerns about (C) in WPF competitions, but I agree that it is not the task of the report to say (C) is not ...
by Fred76
Sun 15 Sep, 2019 9:59 am
Forum: WPF Sudoku Technical Discussion forum
Topic: What is a Sudoku? Report general consultation
Replies: 9
Views: 295

Re: What is a Sudoku? Report general consultation

Hi, I would like to do some comments on this report, perhaps it may help to improve on some points... First, I would like to say that it is a huge and great work from Tom, I would like to thank him for this ! Depending on how this report is used, the WPF has now a chance to do something serious with...
by Fred76
Fri 23 Aug, 2019 9:38 am
Forum: Puzzle Competitions
Topic: Puzzles at the Mind Sports Olympiad in London on Sunday
Replies: 42
Views: 27996

Re: Puzzles at the Mind Sports Olympiad in London on Sunday

I've since found out that the WPF (Prasanna) actively enabled the re-use of the GP Puzzles for competition - heaven only knows what was going through his mind to conclude that was a remotely good idea. hypothesis N°1: He thought that it would be an advertizing for GP competition. He didn't care abo...
by Fred76
Mon 05 Aug, 2019 12:36 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Etymology
Replies: 2
Views: 462

Etymology

Even if we know the arbitrary part of the choice of a puzzle name, I think a good definition should take into consideration the etymology of the puzzle name. For example, I would never say about a hexagonal grid that it is a "latin square", it would be contradictory (I don't think latin squares can ...
by Fred76
Sun 17 Feb, 2019 12:52 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Missing Digit Sudoku
Replies: 1
Views: 1237

Missing Digit Sudoku

29 - missing digit sudoku.png
29 - missing digit sudoku.png (62.46 KiB) Viewed 1237 times
Source: 2015 WSC, Sofia

To me, this is the same question than blackout sudoku: viewtopic.php?f=33&t=1934.
Row/columns and regions containing N cells, thus constituing deficit regions for N+1 symbols to be placed.
by Fred76
Sun 17 Feb, 2019 12:48 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Free Block Sudoku [WSC 2015]
Replies: 1
Views: 1630

Free Block Sudoku [WSC 2015]

28 - free block sudoku.png
28 - free block sudoku.png (55.62 KiB) Viewed 1630 times
Source: 2015 WSC, Sofia

Potential issue: again the lack of regions. Authors are free to chose which part of the grid has a third constraint. This constraint being only to be "deficit" regions (of any size).
by Fred76
Sun 17 Feb, 2019 12:44 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Straight sudoku [WSC 2015]
Replies: 1
Views: 1024

Re: Straight sudoku [WSC 2015]

I think this puzzle has some similarities with Zilina sudoku: viewtopic.php?f=33&t=1931
by Fred76
Sun 17 Feb, 2019 12:42 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Straight sudoku [WSC 2015]
Replies: 1
Views: 1024

Straight sudoku [WSC 2015]

26 - straight sudoku.png Source: 2015 WSC, Sofia Potential issue: lack of regions. Here we have only one "full" regions, and a few other renban groups, which can be described as deficit regions. The major part of the grid has no third constraint (i don't consider a single cell as a deficit region)....
by Fred76
Sun 17 Feb, 2019 12:37 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: 1234 Sudoku [WSC 2015]
Replies: 1
Views: 1134

1234 Sudoku [WSC 2015]

25 - 1234 sudoku.png
25 - 1234 sudoku.png (47.64 KiB) Viewed 1134 times
Source: 2015 WSC, Sofia

Potential issue: repeated digits. This question already raised from other threads, but here it is a bit more extended, with a digit repeated 4 times.
by Fred76
Sun 17 Feb, 2019 12:34 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Jigsaw sudoku [WSC 2013]
Replies: 0
Views: 1117

Jigsaw sudoku [WSC 2013]

24a - jigsaw sudoku.png 24b - jigsaw sudoku.png Source: 2013 WSC, Beijing There are lot of questions merging from this example. It is one of these round I would qualify as "special" that we have seen in some previous wsc. 1. The question about the envelopes: I'm not sure this kind of experience was...
by Fred76
Sun 17 Feb, 2019 12:19 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Ring Sudoku [WSC 2013]
Replies: 1
Views: 1141

Ring Sudoku [WSC 2013]

23 - ring sudoku.png Source: 2013 WSC, Beijing More than the particular example, the question is about geometry of the grid. Here in my opinion all properties are met to say that this puzzle is a sudoku. However, the geometry is unusual (in this particular case, it can be cumbersome to perceive set...
by Fred76
Sun 17 Feb, 2019 12:08 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Character battle [WPF puzzle GP 2018]
Replies: 2
Views: 1593

Re: Character battle [WPF puzzle GP 2018]

I agree that "blank cells" should be treated in the same way we treat repeated symbols in rows/columns and regions. Note that if the number N of characters to be placed equals the size of rows and columns (grid N*N), then we have a no touch sudoku, which I think is well accepted as a sudoku variatio...
by Fred76
Sun 17 Feb, 2019 11:57 am
Forum: WPF Sudoku Technical Discussion forum
Topic: Odd Tapa Sudoku [WPF Sudoku GP 2018]
Replies: 2
Views: 1576

Re: Odd tapa sudoku [WPF sudoku GP 2018]

We haven't discussed Odd Lab(yrinth) Sudoku yet either have we? A very similar idea We haven't. Yes, it is similar in many ways. I tend to think these kind of puzzles are in a grey area. While i don't have a clear argument to say that they are not a sudoku, I would not be very happy to see lot of t...
by Fred76
Sun 17 Feb, 2019 11:39 am
Forum: WPF Sudoku Technical Discussion forum
Topic: Figure sum sudoku [WPF sudoku GP 2017]
Replies: 8
Views: 3096

Re: Figure sum sudoku [WPF sudoku GP 2017]

I think this example is very similar to the battleship sudoku in this thread: viewtopic.php?f=33&t=1961
It has same property of being hybrid with structure placement puzzle.

Fred
by Fred76
Sun 17 Feb, 2019 11:35 am
Forum: WPF Sudoku Technical Discussion forum
Topic: Figure sum sudoku [WPF sudoku GP 2017]
Replies: 8
Views: 3096

Re: Figure sum sudoku [WPF sudoku GP 2017]

Similar to the way Fred has demonstrated on other types, it would be possible to create one of these puzzles where the structure placement constraint is used trivially, making that particular puzzle example a 'primarily' number placement puzzle. I hope we're not going to go as far as saying that, e...
by Fred76
Fri 15 Feb, 2019 11:32 am
Forum: WPF Sudoku Technical Discussion forum
Topic: Burodoku [new example]
Replies: 4
Views: 2048

Re: Burodoku [new example]

One of the most interesting factors (to me) is that you could easily make a variation of this with some numbers missing (and possibly some more bold separations). Then you could make another variant with even more gaps and barriers. And so on, step by step, getting closer and closer to a traditiona...
by Fred76
Fri 15 Feb, 2019 10:07 am
Forum: WPF Sudoku Technical Discussion forum
Topic: Puzzle decorations
Replies: 9
Views: 3346

Re: Puzzle decorations

-------------------------- I think the rest of this comment is just a bunch of rambling nonsense, but I'm going to leave it there in case it means anything to anyone! -------------------------- I guess the point is to show that in some situations you can have puzzles that are almost identical yet s...
by Fred76
Fri 15 Feb, 2019 9:24 am
Forum: WPF Sudoku Technical Discussion forum
Topic: Figure sum sudoku [WPF sudoku GP 2017]
Replies: 8
Views: 3096

Re: Figure sum sudoku [WPF sudoku GP 2017]

detuned wrote:
Thu 14 Feb, 2019 9:00 pm
They look more like tetrominoes to me, but I take the point :)
Oops :roll:
by Fred76
Thu 14 Feb, 2019 12:37 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Puzzle decorations
Replies: 9
Views: 3346

Re: Puzzle decorations

Here is a concrete example. I would like to make analogy of this situation with classic suoku, because I assume we all know the definition of classic sudoku. I would not qualify a thermo-sudoku as classic sudoku. I would not qualify killer sudoku as classic sudoku. Both of these variants contain rul...
by Fred76
Thu 14 Feb, 2019 12:08 pm
Forum: WPF Sudoku Technical Discussion forum
Topic: Puzzle decorations
Replies: 9
Views: 3346

Re: Puzzle decorations

I'm not sure I understand the question fully - as I don't think what you are describing is much of an issue. As far as I can tell, you are concerned about people being confused by rules which are redundant to solving the puzzle. It's not so much the question of confusion than the fact that this con...
by Fred76
Thu 14 Feb, 2019 11:46 am
Forum: WPF Sudoku Technical Discussion forum
Topic: Wrong Puzzles? [WSC 2011]
Replies: 16
Views: 5992

Re: Wrong Puzzles? [WSC 2011]

If we set a boundary on what's allowed and what isn't there will obviously be puzzles very close to the edge. Someone may tweak the rules very very slightly, create a puzzle that's practically identical, yet falls outside the boundary. That feels nonsensical to me, and that's why it's my belief tha...