Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!yale!cmcl2!kramden.acf.nyu.edu!brnstnd
From: brnstnd@kramden.acf.nyu.edu (Dan Bernstein)
Newsgroups: comp.lang.c
Subject: Re: which bits are set
Message-ID: <15598:Dec1804:57:0390@kramden.acf.nyu.edu>
Date: 18 Dec 90 04:57:03 GMT
References: <1990Dec12.205114.2376@uvm.edu> <3047:Dec1618:51:1590@kramden.acf.nyu.edu> <1990Dec17.071404.6544@kithrup.COM>
Organization: IR
Lines: 18

In article <1990Dec17.071404.6544@kithrup.COM> sef@kithrup.COM (Sean Eric Fagan) writes:
> In article <3047:Dec1618:51:1590@kramden.acf.nyu.edu> brnstnd@kramden.acf.nyu.edu (Dan Bernstein) writes:
> >The brute force (i.e., fast) approach is to use a big table.
> Eek.  Why do that?

For speed. The exact answer depends on how you want to store the sets.
If you take my half-facetious suggestion of storing the sets as
integers, it takes 0 operations.

> The only way I can think of to do it faster than the
> presented method is to get rid of the shift and loop:
  [ ... ]
> Takes 32 sequential statements; on some machines, it will take 32
> instructions, while on others, it might take 64.

Eek. Why do you want to make this so slow?

---Dan