Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!ukc!icdoc!achilles!md
From: md@doc.ic.ac.uk (Mark Dawson)
Newsgroups: comp.lang.c
Subject: Re: count of bits set in a long
Keywords: bits set, count of, long
Message-ID: <md.654260871@achilles>
Date: 25 Sep 90 11:07:51 GMT
References: <37545@ut-emx.uucp> <3820@goanna.cs.rmit.oz.au>
Sender: news@doc.ic.ac.uk
Lines: 14

In <3820@goanna.cs.rmit.oz.au> ok@goanna.cs.rmit.oz.au (Richard A. O'Keefe) writes:
>There's a rather nice loop that does one iteration per bit, and works
>for any size ...

Here it is:

	num_set_bits = 0;
	while (word != 0) { /* there must be at least one bit set */
		num_set_bits++;
		word &= (word - 1); /* remove the least significant set bit */
		/* iterate... */
	}

Mark