Path: utzoo!utgpu!water!watmath!clyde!rutgers!cmcl2!brl-adm!umd5!mimsy!chris
From: chris@mimsy.UUCP (Chris Torek)
Newsgroups: comp.lang.c
Subject: Re: Pointers and Arrays
Message-ID: <10403@mimsy.UUCP>
Date: 31 Jan 88 05:36:20 GMT
References: <461@auvax.UUCP> <28700025@ccvaxa> <7159@brl-smoke.ARPA> <1329@laidbak.UUCP>
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 19

In article <1329@laidbak.UUCP> daveb@laidbak.UUCP (Dave Burton) writes:
>K&R, Chapter 5, page 98, Paragraph just above last example:
>"Pointer subtraction is also valid: if p and q point to members of the
> same array, p-q is the number of elements between p and q."

This section of K&R is descriptive, not prescriptive.  What does
the appendix have to say?

At any rate, the number of elements `between' p and q (via p-q) in

	+---+---+---+---+
	| 0 | 1 | 2 | 3 |
	+---+---+---+---+
	 q       p

is easily seen as -2, if you just turn your brain around. :-)
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris@mimsy.umd.edu	Path:	uunet!mimsy!chris