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From: crowter@AI.RL.AF.MIL (John Crowter)
Subject: Re: EQUAL question...
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Organization: Rome Laboratory USAF
References: <1994Oct11.141818@iowasp.physics.uiowa.edu> <37eu3a$p3l@elna.ethz.ch> <crowter.781979970@ai.rl.af.mil>
Date: Wed, 12 Oct 1994 16:51:28 GMT
Lines: 16

>% using append/3 ...

>append([],X,X).
>append([X|R],Y,[X|Z]) :- append(R,Y,Z).

>%call ...

Actually, to cover all cases, I should have included

first_equals_last([X]).
first_equals_last(FirstAndLastEqualList) :-
>   append([X|_],[X],FirstAndLastEqualList).


John Crowter
Rome Laboratory
