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From: jc@atcmp.nl (Jan Christiaan van Winkel)
Newsgroups: comp.lang.c
Subject: flipping bits (was: Re: How to reverse bits...)
Message-ID: <652@atcmpe.atcmp.nl>
Date: 15 Aug 90 07:38:08 GMT
References: <1990Aug14.233308.27889@caen.engin.umich.edu>
Organization: AT Computing, Nijmegen, The Netherlands
Lines: 22

From article <1990Aug14.233308.27889@caen.engin.umich.edu>, by jal@acc (John Lauro):
) In article <1990Aug14.203212.16248@motcad.portal.com> jtc@motcad.portal.com (J.T. Conklin) writes:
)>Another useful table is one that flips the bits 1-for-0,0-for-1.  This
)>is useful for inverting an image.
) 
) How about:   (assuming 8 bit char c) 
)    c=255-c;  or
)    c^=255;

Why make specifications about the charcter's size in bits? There is an
operator in C that is perfectly suited to do the job without having to specify
the number of bits to be flipped:

c = ~c;

which works for chars, ints, longs, ....
JC
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