On 5/22/07, Dan Bron <[EMAIL PROTECTED]> wrote:
Terrence,
You might consider that you can move your index up by more than one at every
iteration.
When you're done with 2&pp you already know that 4 is not a prime candidate.
yes, the next_prime function written by Raul would return 5 when I call
A next_prime 4
but per shootout rules:
http://shootout.alioth.debian.org/gp4/benchmark.php?test=nsievebits&lang=all
* create an array of M bit flags which represent either prime or not-prime
* for each index number
o test the flag value at that index
+ set or clear the flag values at multiples of that
index as necessary
+ if necessary keep and increment a separate count
so basically if (A next_prime 4) is not equal to 4, then I simply go
on to 5 and try
(A next_prime 5) which will equal 5, so then I would continue with
(A process_prime) in that case...
I'm starting to see:
(A process_prime y) ` null_op @. (A is_next_prime y)
I love these naive, verbose, in-elegant algorithms - they let me be
imperative in a functional language...
rec =: {. , 1 , { (] (i.&1@:] $:^:(<#) *) 0 ~: |) (}.~ >:)~
soe =: 2 rec 0: 1} i.
SoE =: I.@:soe
SoE is an abbreviation for what?
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