From: Joost Diepenmaat <joost@...>
Date: 2005-07-17T05:23:09+09:00
Subject: Re: [QUIZ] Sampling (#39)

On Sun, Jul 17, 2005 at 05:01:02AM +0900, Bill Kelly wrote:
> From: "Olaf Klischat" <klischat@cs.tu-berlin.de>
> >
> > See? One number per 200-numbers interval. Every time[1]. This hints at
> > a wrong implementation.
> 
> I used the same approach.  I wasn't sure if it was legal
> or not.  But it was sure easy... :)

I'm sure it was :-)

I'm now down to 1.24 seconds without "cheating":

 time ./sample2 5_000_000 1_000_000_000  >big.txt
 real    1m24.165s
 user    1m17.554s
 sys     0m5.252s
 
 head big.txt 
 30
 64
 65
 760
 1136
 1418
 1536
 1796
 2190
 2306

 tail big.txt 
 999998474
 999998602
 999998676
 999998802
 999998909
 999999036
 999999048
 999999080
 999999196
 999999467
 
 wc -l big.txt
 5000000 big.txt

But I'm pretty much out of ideas on how to make it faster.

Joost.