75392e54c7
git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@757 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
53 lines
960 B
Plaintext
53 lines
960 B
Plaintext
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:- object(driving,
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extends(salesman)).
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:- info([
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author is 'Paulo Moura',
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version is 1.0,
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date is 2000/4/22,
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comment is '.',
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source is 'Example adopted from the Francis G. McCabe L&O documentation.']).
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:- op(400, yfx, ~).
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route(Towns, Route) :-
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presort::route(Towns, Presort),
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drive_around(Presort, Route).
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drive_around(Route~Town1~Town2, Route1~Route2) :-
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!,
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drive_around(Route~Town1, Route1),
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Town1::drive(Town2, Route2).
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drive_around(Town1~Town2, Route) :-
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!,
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Town1::drive(Town2, Route).
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drive_around(Town, Town).
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drive_length(Route, Length) :-
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drive_length(Route, 0, Length).
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drive_length(Route~Town1~Town2, Acc, Length) :-
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!,
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Town1::road_distance(Town2, Length2),
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Acc2 is Acc + Length2,
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drive_length(Route~Town1, Acc2, Length).
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drive_length(Town1~Town2, Acc, Length) :-
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!,
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Town1::road_distance(Town2, Length2),
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Length is Acc + Length2.
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drive_length(_, Length, Length).
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:- end_object.
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