The New Sudoku Players' Forum

by **Karyobin** » Mon Oct 24, 2005 1:04 pm

PaulIQ164 wrote:defense

by **PaulIQ164** » Mon Oct 24, 2005 1:06 pm

Well color me admonished.

by **Karyobin** » Mon Oct 24, 2005 1:55 pm

by **CathyW** » Mon Oct 24, 2005 9:22 pm

Have just sent an email to The Times about the Samurai on p8 of the Sudoku supplement. I'm convinced, like others, that this puzzle must have multiple solutions and they need to print a corrected grid (or a new one) and give an extended deadline.

I got this far with it:

Code: Select all: --- ¦ 48- ¦ --6 ¦ ¦ 2-- ¦ -73 ¦ --- --- ¦ --- ¦ --- ¦ ¦ --- ¦ -1- ¦ --- --4 ¦ --9 ¦ 2-- ¦ ¦ 3-7 ¦ 68- ¦ 1— ––––+–––––+–––––+ +–––––+–––––+–––– 7-2 ¦ -5- ¦ --- ¦ ¦ -3- ¦ -6- ¦ --1 849 ¦ 12- ¦ -35 ¦ ¦ 45- ¦ -28 ¦ --6 -56 ¦ -4- ¦ -2- ¦ ¦ --- ¦ -3- ¦ 9-- ––––+–––––+–––––+–––––+–––––+–––––+–––– 5-3 ¦ -91 ¦ 46- ¦ 958 ¦ 1-3 ¦ -46 ¦ 8— 46- ¦ -3- ¦ 19- ¦ -4- ¦ 5-8 ¦ 39- ¦ --- 291 ¦ 764 ¦ 358 ¦ 217 ¦ 964 ¦ 85- ¦ --7 ––––+–––––+–––––+–––––+–––––+–––––+–––– ¦ 736 ¦ 891 ¦ 452 ¦ ¦ 214 ¦ -7- ¦ 689 ¦ ¦ 985 ¦ -2- ¦ 731 ¦ ––––+–––––+–––––+–––––+–––––+–––––+–––– 3-- ¦ -5- ¦ 621 ¦ 739 ¦ 845 ¦ -3- ¦ --6 --- ¦ -6- ¦ 84- ¦ -6- ¦ --7 ¦ -5- ¦ --- -68 ¦ --- ¦ 57- ¦ -8- ¦ --6 ¦ --- ¦ 5— ––––+–––––+–––––+–––––+–––––+–––––+–––– --6 ¦ --- ¦ 385 ¦ ¦ --- ¦ --3 ¦ 76- 4-- ¦ 186 ¦ 297 ¦ ¦ 653 ¦ 789 ¦ --1 289 ¦ 573 ¦ 164 ¦ ¦ --- ¦ -6- ¦ 9-3 ––––+–––––+–––––+–––––+–––––+–––––+–––– --1 ¦ -32 ¦ 456 ¦ ¦ --2 ¦ 3-- ¦ 8— --- ¦ 61- ¦ 932 ¦ ¦ --- ¦ --- ¦ --- 6-- ¦ 495 ¦ 718 ¦ ¦ 1-- ¦ -25 ¦ ---

Sorry about spacing - first time I've used "code" :!:

I think my central grid is the same as that posted on previous page.

Edited to correct typos in top right grid!

by **Philip Roe** » Mon Oct 24, 2005 9:26 pm

PaulIQ164 wrote:Well, I'm going to leap to the defense here. Alright, so the technique wasn't strictly necessary, but it was an entirely valid way of solving the puzzle, and explained to people a technique that will be needed in some other puzzles. If it'd just said "this puzzles really easy", it wouldn't have been much of a guide, would it? And perhaps that's how Carol solved that puzzle. Maybe she saw the thing with the 2s first. Not everyone solves sudoku like a robot.

My point was that her analysis was faulty. Of course she solved it but she also said it was "fiendish" which is objectively false. A puzzle is simple if it can be solved by forced moves - i.e. by noting at each stage that there is a square into which only one symbol can go or a row, column or "minigrid" only one of whose vacant squares can accommodate a particular missing symbol. To explain a technique you should explain why it is needed. Besides Miss Vorderman has had months to think about it since she has anlysed this same puzzle twice in The Times.

by **PaulIQ164** » Mon Oct 24, 2005 9:26 pm

Yes, it certainly loos familiar. I've tried sending an email to the competition address, as an entry/pointing out the error. So for it's bounced every time though. Shall try again.

by **petef** » Mon Oct 24, 2005 11:01 pm

CathyW,

I'd sent an email as well. The more people that complain, the better the chance of them fixing it.

There is at least one mistake in your solution. Centre left of the top right Su Doku has two threes.

As for the "code", you would do better to better to stick to ISO 8859-1 characters. I'm guessing that you've pasted from Microsoft Word or similar with auto-something left on. Many of your hyphens have been converted to en or em dashes encoded in CP 1252. Less importantly, you've split bars (CP 1252) instead of vertical bars (ASCII and ISO 8859-1).

by **CathyW** » Tue Oct 25, 2005 10:20 am

petef wrote:There is at least one mistake in your solution. Centre left of the top right Su Doku has two threes.

Oops - r4,c2 of the top right grid should have been a 4 and r4,c3 should have been a 5 (givens) - so typos rather than a solving error!

Thanks also for tips on characters when using code - I've now copied grid from a post in the Solving Techniques forum so hopefully all will be well next time.

by **petef** » Tue Oct 25, 2005 12:11 pm

You also have an extra 7 in top right r6c9, which duplicates that in r9c9.

by **CathyW** » Tue Oct 25, 2005 3:17 pm

petef wrote:You also have an extra 7 in top right r6c9, which duplicates that in r9c9.

Oops again - another typo, now corrected above.

by **petef** » Wed Oct 26, 2005 11:53 am

It is reported that the email address for submission is working now. There is still no official word about the ambiguity of the answer, though.

by **PaulIQ164** » Wed Oct 26, 2005 12:21 pm

Yes, I've managed to get an email through since.

by **Enigma** » Thu Oct 27, 2005 9:56 pm

Interestingly, the Times have now removed the first of the Samurai's from their website - the message must have got through:

http://www.timesonline.co.uk/article/0,,18209-1836331,00.html

Text has changed from the printed version "Complete the two Samurai...." to "Complete the Samurai...." in the latest online.

Wonder whether the prizes will now be halved too ?

by **Enigma** » Thu Oct 27, 2005 9:57 pm

Oh - and the deadline has moved to Friday November 4th as well.

by **udosuk** » Fri Oct 28, 2005 7:03 am

Since we are talking about questionable Times articles on last Saturday, in this one about Killer, the author gave 10 tips. The last one bothers me a lot:

10. Beware the 7s: two-square Sum Boxes totalling 7 offer too many possible combinations. Leave them till last.

Common arithmetical sense tells me it would be more approriate if the "7" were replaced by "10", because a 2-cell cage totalling 7 can have 7,8,9 eliminated (just like one that totals 13 can have 1,2,3 eliminated), and I used these instances quite a lot when solving the killers. "Leave them till last" doesn't sound like a helpful or accurate advice. Anybody who thinks otherwise is welcome to respond?

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