2005-05-16

Sudoku

Since Christmas (when Jessica first showed me a fiendish one, which I failed to solve over several days) I've been keen/addicted to Sudoku number puzzles. Here is one, not too hard, in case you don't know what they are:


+---+---+---+
|7.2|...|.8.|
|...|4..|..1|
|.6.|.3.|9..|
+---+---+---+
|..4|...|.7.|
|...|5.1|...|
|.3.|...|2..|
+---+---+---+
|..1|.2.|.9.|
|9..|..7|...|
|.8.|...|3.5|
+---+---+---+


You then have to fill in the numbers 1-9 in each row, each column, and each 3x3 sub-square. Note the symmetry of the initial placement: this doesn't appear to be essential, and doesn't imply any symmetry in solving it.

They first appeared in the UK in the Times, then the Torygraph, and I grew annoyed that the Grauniad (which we get) didn't have them, I was reduced to scrounging Times's from various places (notably CB1, where it is now traditional for Rob not to do them...). Then the Grauniad just a week ago succumbed, good, about time too, pity they had to ponce around with stuff about how theirs were human-generated hand hence much better (they are slightly different in style, but not clearly any better). Apparently they are even in the Sun, though presumably not the difficult versions :-).

And... they originate in Japan, land of mystic east (cue tinkly glasshopper type music). Except... I asked JA at EGU if he had ever seen one (he works in Japan) and... no, he never had.

I can do the fiendish ones now. Half an hour, on a good day.
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2 comments:

  1. James Annan18/05/2005, 13:38

    Apparently sudoku really do exist in Japan, so my language teacher tells me.

    By the way, as well as being considered an attractive flower it its own right, OSR is a spring-time delicacy here, like a slightly mustard-flavoured version of broccoli.

    I can't see it catching on world-wide, but it's not the nastiest thing I've eaten, by a long way.

    James

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  2. Anonymous22/06/2005, 19:03

    Hi,

    Bit of an obvious plug here, but I've developed an online Sudoku Assistant at

    www.sudokusan.com

    It's a free site, it has four daily graded puzzles, it uses logic to solve them and if you need it, it tries to give 'intelligent' advice about what you can do next.

    It's a pretty new site so all feedback and ideas welcome.

    cheers,
    Alastair

    p.s. if you fancy a challenge, the Atrocious level is a lot harder than anything you can currently see in the UK papers!

    ReplyDelete