> Not bad, but not especialy clever.
> 
> 
>>I am aware that the non-native and object-oriented ruby code 
>>won't be as
>>fast as the c++ one, but I didn't expect such a gap.
> 
> 
> Let's look at some numbers:
> 
> 
>>ruby -rubygems sudoku-solver.rb
> 
> time elapsed: 29.703 sec.
> count: 127989
> 3 6 2 4 9 5 7 8 1
> 9 7 1 6 2 8 5 3 4
> 8 5 4 1 3 7 9 6 2
> 2 9 3 5 6 4 1 7 8
> 5 1 7 3 8 2 4 9 6
> 6 4 8 9 7 1 2 5 3
> 7 2 9 8 1 3 6 4 5
> 1 8 5 7 4 6 3 2 9
> 4 3 6 2 5 9 8 1 7
> 
> 
>>ruby -rubygems quiz43.rb
> 
> time elapsed: 0.156 sec.
> +-------+-------+-------+
> | 8 3 2 | 4 9 5 | 7 6 1 |
> | 9 7 5 | 6 1 2 | 8 3 4 |
> | 1 6 4 | 7 3 8 | 9 5 2 |
> +-------+-------+-------+
> | 2 9 3 | 5 7 4 | 1 8 6 |
> | 6 1 7 | 8 2 3 | 4 9 5 |
> | 5 4 8 | 9 6 1 | 2 7 3 |
> +-------+-------+-------+
> | 3 2 9 | 1 5 7 | 6 4 8 |
> | 7 8 1 | 3 4 6 | 5 2 9 |
> | 4 5 6 | 2 8 9 | 3 1 7 |
> +-------+-------+-------+
> 
> 
> So ruby is 3 times faster than C. *g*
> No bad.
> 
> (look at my last solution on http://www.rubyquiz.com/quiz43.html
> for the code, but this last one is realy only optimized for speed
> so its ugly - perhaps look at the other ones also)
> 
> 
>>Thanks for comments.
>>
>>Alexis.
> 
> 
> cheers
> 
> Simon
> 

Sure I know that my recursive algorithm is the simplest and most
unefficient way to solve a sudoku, but it was not my intention to do it
as optimal as possible. I just wanted to see if such a deep recursion
can be done by ruby within reasonable time. And as stated, at first
sight I was surprised about the results.
Thanks for all your comments (thanks to the "mean" ones too :-) ), it
now makes perfect sense.

Alexis.