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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: portable way to get highest bit set?
Date: Sat, 14 Oct 2023 19:05:05 -0700
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jak <nospam@please.ty> writes:

> unsigned long h_bit(unsigned long val)
> {
>     int i;
>     for(i = 0; val > 1; val /= 2, i++);
>     return val << i;
> }

A nice compact solution.  I like the way it
naturally deals with the case when val is zero.