Killer sudoku: Repeated digits are allowed!!!!

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Killer sudoku: Repeated digits are allowed!!!!

From today's Times (12/9/05):

'Within each dotted-line "shape", a digit CAN be repeated if the normal row, column and 3x3 box rules are not broken.'
silvercar

Posts: 24
Joined: 05 July 2005

yes,just seen that. strange though as all the ones printed so far have not used this rule. does this mean multiple solutions now then? i have to say i always assume no duplicates and have had no problems so far. (not very hard again today i thought!!)

Also did you see the hint!! i had to laugh!

dom
domt

Posts: 16
Joined: 01 September 2005

Oh yes, the hint, 'for two weeks only!'

In the original article about Killer Su Doku (Times 2, 31 August) it was stated that 'in the case of three joined squares, if the printed number is 6, the only combination possible is 1, 2 and 3.' Surely 4, 1 and 1 would be a possibility, unless the rule in today's paper has only just been introduced.
possum

Posts: 86
Joined: 05 April 2005

Yes, from perusing today's Times I got the distinct impression that comments have been sent in as to the severity of the Killers. Top hint though - 'for two weeks only' - maybe the rule'll change after that!

On a more serious note, I was a bit surprised to see the clarification of the 'duplicate entry' scenario. It would seem to rail against everything that we sudokuka hold sacred, though not breaking 'the rule' per se. The original explanation of the 'Killer' rules from about ten days back would seem to imply that each dotted area cannot contain duplicates, which is obviously decried by today's little revelation.

possum wrote:In the original article about Killer Su Doku (Times 2, 31 August) it was stated that 'in the case of three joined squares, if the printed number is 6, the only combination possible is 1, 2 and 3.' Surely 4, 1 and 1 would be a possibility, unless the rule in today's paper has only just been introduced.

Absolutely. I am led to conjecture that, this point having been raised several times by correspondents, the paper simply wrote that statement without reference to the puzzle planners (or the above quotation), and not fully understanding the implications of their assertion. It'll be interesting to see what tso makes of this. Maybe he'll just spin round snarling and bounce off into the distance.

Challenge: Find a 'Killer' which has two distinct solutions - one without duplicating entries and one with.
Karyobin

Posts: 396
Joined: 18 June 2005

And what was the deal with the three encosures that were already filled in? It wasn't even like they were all necessary - you could fill in the ones in the top-right box straight away anyway!
PaulIQ164

Posts: 533
Joined: 16 July 2005

Exactly - hence my belief that people have complained.
Karyobin

Posts: 396
Joined: 18 June 2005

The bottom right numbers were necessary though, surely?

They HAD to be ones and twos so it would have been possible to solve the rest of the puzzle without that info, but I can't see any way it would have been possible to determine which way round they went.

3 cells in a straight line totalling 24 must be 7/8/9. There's two of those (top left and bottom right).

2 cells totalling 16 must be 7 & 9.

Of course Friday's killer had the biggest total I've seen. 42 in 7 cells in one box meant the other two cells in that box had to be 1 & 2.

I'm very new at this game, but I'm glad I've spotted many of the tricks all by myself.
CarolineMary

Posts: 3
Joined: 09 September 2005

possum wrote:In the original article about Killer Su Doku (Times 2, 31 August) it was stated that 'in the case of three joined squares, if the printed number is 6, the only combination possible is 1, 2 and 3.' Surely 4, 1 and 1 would be a possibility, unless the rule in today's paper has only just been introduced.

If the three joined squares are in an L shape that crosses a 'box boundary', I would say that is possible.

To be honest, I never worried about it. If solving unambiguous groups using arithmatic and normal Sudoku techniques forces a repeated digit into a totalled group then I think it will be obvious. In today's puzzle, I see two "T shaped" groups of 4 that could at first glance have possibly had repeating digits. But then, to balance that, they had two "groups" of 1 cell totalling 7 each. Oh, gosh I wonder what number I should put in there, then? [/sarcasm]
CarolineMary

Posts: 3
Joined: 09 September 2005

Yep, this is getting silly.

Today's 'clarification' that repeated digits are allowed in any outlined shape doesn't make sense. Has anyone yet found an instance of where this has been possible in a puzzle published to date?

And today's puzzle was trivially easy, and nowhere near 'moderate' standard.

What's going on? There's a serious lack of quality control being applied.
roger888

Posts: 19
Joined: 27 June 2005

I told you - sadly, we're the freaks who don't mind getting stuck on a puzzle for an hour/day or so. The readers Out There don't like feeling stupid, so rather than persevere and learn, they complain when they can't do a puzzle, which sadly leaves us lot largely out in the cold - our challenges decrease whilst the media give us another example of 'dumbing-down', and thus maintain/increase their circulation. Speaking as a quizmaster, I could easily set questions that very few people could answer (Who led the vaward at Agincourt?) That's a really effective way of shutting a quiz down, almost overnight.

In response to CarolineMary's points, it would certainly be interesting to run the puzzle again without the initial clues, though I strongly doubt they are essential as you suggested. Also, as tso commented earlier in these discussions, as it was originally stated that a total of 6 must be made from 1, 2 and 3, it is implicit that 4, 1 and 1 are not viable opotions. Otherwise they wouldn't state that the correct combination was 1, 2 and 3, would they?

But as you say, it really isn't worth worrying about in a practical sense, it just bothers the theorists.
Last edited by Karyobin on Mon Sep 12, 2005 12:13 pm, edited 2 times in total.
Karyobin

Posts: 396
Joined: 18 June 2005

I agree! Today's "Killer" should have been labelled Very Easy.

I think it's useful to have clarification that digits could be repeated provided normal Sudoku rules aren't broken but none of the puzzles so far have had repeated digits. All adds to the possibilities and, in theory, it might make the puzzles more challenging.
CathyW

Posts: 316
Joined: 20 June 2005

Karyobin wrote:Yes, from perusing today's Times I got the distinct impression that comments have been sent in as to the severity of the Killers. Top hint though - 'for two weeks only' - maybe the rule'll change after that!

On a more serious note, I was a bit surprised to see the clarification of the 'duplicate entry' scenario. It would seem to rail against everything that we sudokuka hold sacred, though not breaking 'the rule' per se. The original explanation of the 'Killer' rules from about ten days back would seem to imply that each dotted area cannot contain duplicates, which is obviously decried by today's little revelation.

possum wrote:In the original article about Killer Su Doku (Times 2, 31 August) it was stated that 'in the case of three joined squares, if the printed number is 6, the only combination possible is 1, 2 and 3.' Surely 4, 1 and 1 would be a possibility, unless the rule in today's paper has only just been introduced.

Absolutely. I am led to conjecture that, this point having been raised several times by correspondents, the paper simply wrote that statement without reference to the puzzle planners (or the above quotation), and not fully understanding the implications of their assertion. It'll be interesting to see what tso makes of this. Maybe he'll just spin round snarling and bounce off into the distance.

Challenge: Find a 'Killer' which has two distinct solutions - one without duplicating entries and one with.

I think you've hit the nail exactly on the head. If and when they *do* publish a puzzle that breaks the rule, we'll still have the nonsenseical comments about 1-2-3 and 7-8-9 on the record.

The puzzle I posted August 22nd has three solutions, two that have duplications. All three solutions are posted by catilina in the thread.
http://forum.enjoysudoku.com/viewtopic.php?t=995&postdays=0&postorder=asc&start=0
tso

Posts: 798
Joined: 22 June 2005

still pushing this "CAN be repeated" today (13/9) but again came up short if you know what i mean. oh well, maybe one day.

Oh by the way Karyobin, was it the Duke Of York
domt

Posts: 16
Joined: 01 September 2005

When the Times originally introduced these, they strongly implied that the puzzles were sourced from Nishio Tetsuya's 'puzzle studio'. Further evidence is that today's puzzle is credited to Hamada Tsuyoshi, who is presumably the originator of Hamada's Logic (BTW: does anyone have an explanation of this?), and is described as one of Nishio's 'apprentices'.

So...

Does anyone have a line in to Nishio? Why can't someone ask him to clarify the position? (And while they're at it, ask for an explanation of the bizarre ratings the Times is now giving to the puzzles).
roger888

Posts: 19
Joined: 27 June 2005

domt wrote:Oh by the way Karyobin, was it the Duke Of York

Yes, it was. You win a lolly and a book of 'Killer' sudoku, along with a set of contradictory and nonsensical instructions.

P.S. Instructions to the book, not the lolly.
Karyobin

Posts: 396
Joined: 18 June 2005

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