note
cforde
In the pursuit of efficiency I have come up with a slightly different implementation: Carl1.
In Carl2 I tried to optimize at the expense of a few more characters.
<p>
On my WinNT PIII 800Mhz machine with ActiveState 522 both of these are faster than ase's Bit Vector implementation.
<p>
<code>
Carl1:
@p=(1);for(2..10000){if(!$n[$_]){push@p,$_;for($k=$_*$_;$k<=10000;$n[$k]=1,$k+=$_){}}}
Carl2:
@p=(1,2);for($_=3;$_<=10000;$_+=2){if(!$n[$_]){push@p,$_;for($k=$_*$_;$k<=10000;$n[$k]=1,$k+=$_){}}}
</code>
One thing that I found interesting is that for n less than about 10,000, Carl1 is significantly faster than Carl2.
The loop control overhead must be pretty significant.
<p>
Have fun,<br>
Carl Forde
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