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Path: utzoo!watmath!wateng!pdbain
From: pdbain@wateng.UUCP (Peter Bain)
Newsgroups: net.lang,net.lang.pascal
Subject: Why compare pointers in Pascal?
Message-ID: <1920@wateng.UUCP>
Date: Mon, 28-Jan-85 11:17:13 EST
Article-I.D.: wateng.1920
Posted: Mon Jan 28 11:17:13 1985
Date-Received: Tue, 29-Jan-85 05:41:39 EST
References: <3161@ucla-cs.ARPA> <335@snow.UUCP>
Reply-To: pdbain@wateng.UUCP (Peter Bain)
Organization: U of Waterloo, Ontario
Lines: 11
Xref: watmath net.lang:1317 net.lang.pascal:210
Summary: 

Say I had a set of records, which I represented as a vector of pointers.
Suppose further that I wanted to test for set membership by comparing
pointers. If I keep the vector sorted by increasing pointer value,
I can do the test in O(lg(N)), using a binary search, but I need
< and > on pointers. If all I have is == and !=, it takes O(N) time.
-- 
   - peter bain
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