## Killer - I don't believe it!

All about puzzles in newspapers, magazines, and books

### Killer - I don't believe it!

The rules changed again today - digits CAN be repeated in shapes.

Does anyone know when the organgrinder gets back from holiday to replace the monkey? Has anyone had any response from The Times on this ongoing mess?
Bigtone53

Posts: 413
Joined: 19 September 2005

Oh, poor poor Times. They just can't work it out, can they?
PaulIQ164

Posts: 533
Joined: 16 July 2005

### some frustration here

Having kept the 5 prize killer sudoku published on 31 August for a rainy day, I only tackled them a few days ago.
Applying what (before I was aware of these discussions) I had assumed was a clever trick of being able to duplicate numbers in a group as long as normal rules are met, I came across an identical problem at the end of both the tricky and the deadly. Completing the final left hand corner was only possible if the totals were wrong in two of the groups. I had a perfect solution for a normal Sudoku, had not broken any rule, but had reached an incorrect solution for a 'Killer'. I thought there was supposed to be one solution only.
Having read through these discussions yesterday, the weight of opinion was that duplicates were not allowed, so I checked my solutions to all 5 killers. Sure enough, the only two where I had made use of the duplicates allowed scenario were the two that had not worked out.
So, I completed them again, disallowing duplicates and found that they worked fine.
This made me happy because I now knew (definitively) that duplicates are not allowed in a group. I would now be able to continue confidently.
However, as BigTone points out, the Times' explanation today has changed from its previous ambiguous explanation (with its impossible double negative), to say that "a digit CAN be repeated ...".
At least it is not ambiguous, but AAAAARGH!!!
byfe59

Posts: 3
Joined: 22 September 2005

Come on, it's obvious, isn't it ?

You can't have the same rule on any given row of days. Wait 9 days and you'll be ok. Put them in a box, and again, they won't be allowed to come up with the same rule.
Enigma

Posts: 53
Joined: 14 June 2005

I just wonder what they're going to say in the Killer Sudoku book that's coming out. Is the publishing delay so that they can make up their minds?
jf27

Posts: 34
Joined: 18 September 2005

byfe59 wrote:This made me happy because I now knew (definitively) that duplicates are not allowed in a group.

Actually, at this point, you don't. You only know that when you chose not to apply the "duplicates aren't allowed" rule on these two Killer sudoku, they didn't work out. Sadly that doesn't imply anything of the sort for the multitude of other Killer sudoku out there.

Sorry but I just got back from a job interview/thingy and I'm all wide awake now. Quiz night tonight, the Stella Pixie beckons...
Karyobin

Posts: 396
Joined: 18 June 2005

I'd be interested to see these half-solutions, because I'd thought I solved them all without using the rule at all.
PaulIQ164

Posts: 533
Joined: 16 July 2005

Happy to oblige Paul.

Tricky:

658 923 147
937 184 256
142 567 389

375 298 614
896 471 532
214 356 798

789 635 421
423 719 865
561 842 973

The group with duplicates is the group of 5 digits totalling 21 running down from the bottom left of the middle top - 52464.
The bottom left was the last area completed - the 19 group works fine but the two 13 groups have to contain digits adding up to 16 and 10.

457 689 123
912 374 685
386 512 794

591 248 367
278 136 459
634 795 812

825 463 971
763 951 248
149 827 536

The group with the duplicates is again a 21 group (coincidence??) with five digits, starting in the middle of the top left area - 18651.
Again the problem arose with the last section completed (suppose it would be) - the bottom left area where my 20 group adds up to 21 and my 15 group adds up to 14.
byfe59

Posts: 3
Joined: 22 September 2005

But, even assuming there's not a duplicates rule, if you got to a position where the puzzle was incompletable, you must have made a mistake at some point (placed a number that you didn't know for certain to be correct). As an analogy, if you ignored the 3x3 box rule in a regular sudoku, and never guess, you won't ever get to a position where there's no way to complete the puzzle, you'll just get to a point where there isn't a logical next move to make. What I assume you've done is got caught up in the cleverness of your trick, and put in a duplicate-digit solution to an area that you didn't know for certain had to be correct.

I think.
PaulIQ164

Posts: 533
Joined: 16 July 2005

Hi Paul
I'm pretty sure I got there without making a mistake and I would never guess or chose a 50-50.
I'll see if I can retrace my steps.
byfe59

Posts: 3
Joined: 22 September 2005

Enigma wrote:Come on, it's obvious, isn't it ?

You can't have the same rule on any given row of days. Wait 9 days and you'll be ok. Put them in a box, and again, they won't be allowed to come up with the same rule.

And I thought Enigma was joking. Yet another change today.
Bigtone53

Posts: 413
Joined: 19 September 2005

But..at least todays rules are correct and make sense.
Lets hope they stay that way
boaz

Posts: 26
Joined: 31 August 2005

Todays rules were better, i can't believe no-one at the time actually read the alterations to the rules before sending them out, i mean come on

changing CAN to CANNOT does not clarify the situation, thank you times for writing something that makes sence.
Pi

Posts: 389
Joined: 27 May 2005

Also - when did they print solutions and winners to the competition when they printed the Killers on one page?
Jules

Posts: 7
Joined: 23 September 2005

Jules wrote:when did they print solutions and winners to the competition when they printed the Killers on one page?

I haven't seen it. I have sent them 2 emails about this a while ago. I have heard nothing. I want to know if I won anything! Maybe they are playing for time since the prize - the book - has been delayed?
zebedeezbd

Posts: 60
Joined: 14 September 2005