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From: ken@rochester.UUCP (Ken Yap)
Newsgroups: net.lang.c
Subject: Re: reversing a mask
Message-ID: <4069@rochester.UUCP>
Date: Sun, 25-Nov-84 01:59:27 EST
Article-I.D.: rocheste.4069
Posted: Sun Nov 25 01:59:27 1984
Date-Received: Mon, 26-Nov-84 02:02:48 EST
References: <1@imd.UUCP> <469@ncoast.UUCP> <691@gloria.UUCP>
Reply-To: ken@seneca.UUCP (Sue-Ken Yap)
Organization: U. of Rochester, CS Dept.
Lines: 13
Summary: 

>What's the fastest way to reverse a 16-bit mask in C?  In 68000 asl?

Actually the 65536 combination answer wasn't too far from a plausible
method - split the word up into 2 8 bit bytes and then do two lookups.
Then swap bytes.  This way you only need one 256 byte table.

You could do lookups on nybbles, etc, ad nauseum.
-- 
	Ken Yap

	UUCP:	(..!{allegra, decvax, seismo}!rochester!ken)
	ARPA:	ken@rochester.arpa
	USnail:	Ken Yap, Dept. of Comp. Sci., U. of Rochester, NY 14627.