8b74eb8b2b
git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1260 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
37 lines
493 B
Prolog
37 lines
493 B
Prolog
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my_length(List, Length) :-
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integer(Length) ->
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Length >= 0,
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my_make_list(Length, List)
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;
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my_length(List, 0, Length).
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my_make_list(0, []):-
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!.
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my_make_list(N, [_| Tail]):-
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M is N-1,
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my_make_list(M, Tail).
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my_length([], Length, Length).
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my_length([_| Tail], Acc, Length) :-
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Acc2 is Acc + 1,
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my_length(Tail, Acc2, Length).
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:- dynamic(pred_plain/0).
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db_test_plain :-
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repeat(100),
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assertz(pred_plain),
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fail.
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db_test_plain :-
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retract(pred_plain),
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fail.
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db_test_plain.
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