The New Sudoku Players' Forum

[Kakuro.info]

Hi,

I don't know if any of you have seen Kakuro yet, it's similar to Sudoku but a bit trickier. There are some free puzzles here :

http://www.kakuro.info

[PaulIQ164]

Oh yes. They put those in that Sudoku Magazine that's out. It's quite a nice puzzle. The most obvious similarity is to "killer" su doku, but in any case I don't like it as much as regular sudoku.

[lunababy_moonchild]

It looks very interesting, which sounds very condescending but I tend to keep away from these and killer soduko's because addition gives me a headache (and I usually add it incorrectly anyway )

Luna

[Karyobin]

Right then. Just spent half an hour on the 'Kakuro Puzzle Number 4'. I successfully placed four numbers, sorted out a few possible candidates before the thought hit me - "Bugger this for a game of soldiers!"

I'm afraid that, for me, the number of possibilities quickly became so huge that it felt like nothing more than an exercise in number-crunching and, as such, T & E. As I said a long time ago, if I don't know why a number should be somewhere, I'm not interested in placing it.

And as Paul said, they're nice, but if I want to solve something which involves that much T & E I'll use Excel.

(By the way, if anybody can describe to me a strictly logical way to solve the puzzle I'm talking about, and can explain it - well then, I might have to completely revise my opinions.)

[Pi]

I am working on one and i like the idea

I don't think that it is as good as killer sudoku though


and by the way i was delighted that the one in the times today had no candidates

[tso]

First, Cross Sums puzzles aka Kakro are ubiquitious in US puzzle magazines and have been for at least half a century. You guys are acting like you've never seem one. They're *everywhere*. Google "cross sums" and "kakro" to start. Read http://en.wikipedia.org/wiki/Kakro

Second, no, the don't require T&E or guesswork.

Third, I hate them. Unlike Number Place, they generally end with a whimper rather than a bang. What I mean is, there is usually a sticking point in Sudoku (of sufficient difficulty) -- once that "next logical step" is found, everything else falls like dominos. This happens to a far less degree in Cross Sums. It's more like a Cross Word puzzle in that respect. There are less 'long range effects'. What happens at the bottom right may not help in anyway in the upper left. However, the fact that I find a lack of depth is these puzzles compared with Sudoku could in fact have more to do with the fact that I don't like them and am not proficient in solving them than anything else.

Fourth, they are very, very popular in Japan. My personal experience is that you can find harder Cross Sums in Japanese magazines than in US.

Fifth, "killer" aka "Samunamupure", a relatively recent invention, is *explicitly* a hybrid of Cross Sums and Number Place. See the inventors own words here: http://www7a.biglobe.ne.jp/~sumnumberplace/44319072/

So first there was Cross Sums aka Kakro, then Number Place aka Sudoku, then Killer aka Samunamupure. The first two are very popular, the third is quite rare. Many other Sudoku variants are currently more popular

Oh, and contrary to the myth put out by UK media, crossword and other types of word puzzles are more popular in Japan than Sudoku and the rest of the logic genre.

[garethm]

The logic is similar to Sudoku but with an extra level of elimination - you need to look for combinations that can make the required total. I've put a table on my site which helps (www.dokakuro.com) - using this you can see that for example the clue '6' placed next to 3 cells has to be 1 + 2 + 3, ie you can put '123' as the only pencilmarks in these cells. That's fairly obvious but some of the larger totals and clue runs aren't so easy!

Then the rest of the puzzle is somewhat similar to Sudoku, but with less scanning round the rest of the grid. It can take longer to find out you've gone wrong, though! I normally find in Sudoku I notice within a couple more moves...

Anyway, I've put up a website player that makes it much easier to experiment and solve it online. It's not completely finished (I want to put a bit more logic into the 'helper' aids) but it's working and usable. It's at
www.dokakuro.com - only one puzzle in it so far but more coming soon I hope! (If I can get my creator working better ). There's a similar thing over at www.dosudoku.com for Sudokus too, if anyone's interested.


Gareth

[Enigma]

I spotted it in one of the monthly Sudoku mags by Puzzler just a couple of days ago and gave it a go. Like some of the others, I didn't like it as much as killers - just not as elegant. I didn't find it needed T&E, but there were too many rows/columns where there could only be one combination of digits in it, so it may have been dumbed down as an initial teaser to the type of puzzle (eg 3 cells with total 6, 4 with 10/11 or 29/30, 5 with 34/35 etc).

I'd still say I prefer original difficult/fiendish Sudokus and Samurais.. I think even the killers have too many inherrent clues unless you have loads of cages with 4+ numbers in each. I don't think any of the recent killers have taken more than 7-8 mins, which just isn't long enough in my mind to get a sense of satisfaction from cracking them. I really enjoyed having another crack at one of the harder early Samurais from the Times - I'd love to see more of them.

[lunababy_moonchild]

You guys are acting like you've never seem one.

No I haven't seen one before. 'Scuse me for never having seen every puzzle ever invented.

Luna

[Karyobin]

Me either. I look forward to perusing this year's edition of Grottles Guide to Puzzles and Conundra. Been wondering what tso stood for for ages. ;-)

"They don't require T & E or guesswork"?

I'm afraid that I can follow Forcing Chains and the like when applied to sudoku, but the sheer number of available options leave the puzzle I mentioned, whilst perhaps not requiring guesswork per se, with too many avenues to enjoy exploring. I mean, there's walking in the woods and there's getting drunk, spinning round and chasing rabbits.

'It don't mean a thing if it ain't got that', etc...

P.S. We teensy-seaside-town-dwelling-Northerners don't have a lot of access to the august publications to which you refer. The only puzzle magazines I've ever seen are the ones stuffed full of wordsearches, spot-the-difference and facile crosswords and invariably have a picture of a dog holding a joke telephone on the cover. Or something.

P.P.S. Was that a correct application of 'per se', maybe I should check with 9X9?

[Enigma]

Sorry. "Per se" is not a valid term. It's got 2 letter e's on the same row.

And as for the Sudoku mag, it's about A5 size and I've picked up a copy in both Sainsburys and WH Smiths. You may have been looking in the wrong Smiths (John or Samuel) if you're from Up North. And it was the June or July issues, I think. Probably took a month off in August Try the back catalogue.

[MCC]

Karyobin I believe your usage of 'per se' is correct.

In the book 'Latin Words,Phrases,Mottoes,Quotations in common English Usage' there is:

per se: by him-, her-, itself, themselves.

Also, &: ampersand: corruption of 'and per se and'.

Lesson over.

[Karyobin]

Top stuff. Thought it was.