On Sun, 25 Jan 2009 17:03:13 -0500, Warp wrote:

> Jim Henderson <nos### [at] nospamcom> wrote:
>> On Sat, 24 Jan 2009 06:08:51 -0500, Warp wrote:
> 
>> > Jim Henderson <nos### [at] nospamcom> wrote:
>> >> I've done several where there were clearly multiple solutions -
>> >> particularly at easier degrees of difficulty.
>> > 
>> >   Did you actually try to solve it in different ways?
> 
>> Yes.
> 
>   I mean: did you get two different solutions, or did you arrive at the
> same solution by two different paths?

I got two different solutions.

Jim

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scott wrote:
>>  If trial-and-error was acceptable in a sudoku, then you could just as
>> well give an empty sudoku grid for someone to solve.
> 
> I was assuming (as do most others I think) that sudoku problems only 
> have 1 unique solution.  What would be the point of an empty grid?

To make sure your solving algorithm works! :)

-- 
   Darren New, San Diego CA, USA (PST)
   "Ouch ouch ouch!"
   "What's wrong? Noodles too hot?"
   "No, I have Chopstick Tunnel Syndrome."

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Jim Henderson <nos### [at] nospamcom> wrote:
> I got two different solutions.

  Then it sounds like that sudoku was broken. (How can they, for example,
give the solution to it if it has more than one?)

-- 
                                                          - Warp

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On Mon, 26 Jan 2009 13:56:21 -0500, Warp wrote:

> Jim Henderson <nos### [at] nospamcom> wrote:
>> I got two different solutions.
> 
>   Then it sounds like that sudoku was broken. (How can they, for
>   example,
> give the solution to it if it has more than one?)

No, it wasn't broken.

How many different possible solutions are there for filling in a Sudoku 
if no spaces are filled in?  Now fill in 6 of the spaces.  How many 
unique solutions result in numbers in those pre-filled conditions?

Logically, it *has* to be possible to come up with multiple solutions, 
otherwise there would only be *one* way to fill in the boxes to start 
with.

Jim

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On 26-Jan-09 9:39, scott wrote:
>>  If trial-and-error was acceptable in a sudoku, then you could just as
>> well give an empty sudoku grid for someone to solve.
> 
> I was assuming (as do most others I think) that sudoku problems only 
> have 1 unique solution.  What would be the point of an empty grid?
> 
>>  The principle in sudoku puzzles is that they can be solved without 
>> having
>> to guess anything. The chain of required deductions may go very deep in
>> the hardest sudokus, but it's always possible to solve it without having
>> to guess.
> 
> However most people would rather use trial and error than go very deep 
> in logical deductions.  ie write a 3 in lightly and fill in a few more 
> squares based on that, oops no that doesn't work, original square must 
> have been a 6 then.  

You can do the simple ones by trial and error but that would take too 
much time for the more difficult ones. There you need deduction to 
complete it in a reasonable time. Applying deduction for the simple ones 
makes those rather boring. More time spend on writing down the numbers 
than on actually thinking and that irritating pen is in the way when 
write so you can not see part of the puzzle, annoying. I stopped doing 
the simple ones. ;)

> Isn't trial and error a form of deduction anyway?

I don't think it is. It is, however, a general and well known solving 
strategy.

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On 26-Jan-09 14:46, Mike Raiford wrote:
> Nicolas Alvarez wrote:
> 
>> the lost r's migrate southwest, causing a Texan to 'warsh' his car and
>> invest in 'erl wells'."
> 
> God help me if I ever talk like that.
> 
> We need an agreed upon pronunciation standard that A) is easy to 
> understand for the majority of folks on here, 
agreed

> and B) Won't get Warp's hackles up.

<innocently> why? </innocently>

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andrel wrote:
> On 26-Jan-09 14:46, Mike Raiford wrote:
>> Nicolas Alvarez wrote:
>>
>>> the lost r's migrate southwest, causing a Texan to 'warsh' his car and
>>> invest in 'erl wells'."
>>
>> God help me if I ever talk like that.
>>
>> We need an agreed upon pronunciation standard that A) is easy to 
>> understand for the majority of folks on here, 
> agreed
> 
>> and B) Won't get Warp's hackles up.
> 
> <innocently> why? </innocently>

So we don't get Warp's hackles up when someone innocently asks how 
something is pronounced. That's why.

Can you think of a better reason? :)

-- 
~Mike

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On 26-Jan-09 21:40, Mike Raiford wrote:
> andrel wrote:
>> On 26-Jan-09 14:46, Mike Raiford wrote:
>>> Nicolas Alvarez wrote:
>>>
>>>> the lost r's migrate southwest, causing a Texan to 'warsh' his car and
>>>> invest in 'erl wells'."
>>>
>>> God help me if I ever talk like that.
>>>
>>> We need an agreed upon pronunciation standard that A) is easy to 
>>> understand for the majority of folks on here, 
>> agreed
>>
>>> and B) Won't get Warp's hackles up.
>>
>> <innocently> why? </innocently>
> 
> So we don't get Warp's hackles up when someone innocently asks how 
> something is pronounced. 
<innocently> I though that was the sole object of it </innocently>

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andrel wrote:
> On 26-Jan-09 21:40, Mike Raiford wrote:
>> andrel wrote:
>>> On 26-Jan-09 14:46, Mike Raiford wrote:
>>>> Nicolas Alvarez wrote:
>>>>
>>>>> the lost r's migrate southwest, causing a Texan to 'warsh' his car and
>>>>> invest in 'erl wells'."
>>>>
>>>> God help me if I ever talk like that.
>>>>
>>>> We need an agreed upon pronunciation standard that A) is easy to 
>>>> understand for the majority of folks on here, 
>>> agreed
>>>
>>>> and B) Won't get Warp's hackles up.
>>>
>>> <innocently> why? </innocently>
>>
>> So we don't get Warp's hackles up when someone innocently asks how 
>> something is pronounced. 
> <innocently> I though that was the sole object of it </innocently>

Ahh, I missed the overall goal then. Carry on.

-- 
~Mike

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Jim Henderson <nos### [at] nospamcom> wrote:
> No, it wasn't broken.

> How many different possible solutions are there for filling in a Sudoku 
> if no spaces are filled in?  Now fill in 6 of the spaces.  How many 
> unique solutions result in numbers in those pre-filled conditions?

> Logically, it *has* to be possible to come up with multiple solutions, 
> otherwise there would only be *one* way to fill in the boxes to start 
> with.

  If there were multiple solutions to sudoku puzzles, it would be
impossible to give an answer, like most sudoku magazines have: The
given answer would only be *one* of the solutions and wouldn't really
help.

  That's the marvel of sudoku: There's only one solution, but it's hard
to find because you need to make a lot of deductions in order to come up
with the correct numbers. The harder the sudoku is rated, the deeper the
chain of deductions you need.

-- 
                                                          - Warp

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