commit 27d0d019ca56ace2a63278f698353fe5d9658a29
Author: ryuga4 <ryuga4@o2.pl>
Date:   Mon May 27 22:58:09 2019 +0200

    init

diff --git a/expert.pl b/expert.pl
new file mode 100644
index 0000000..d026cc9
--- /dev/null
+++ b/expert.pl
@@ -0,0 +1,87 @@
+
+
+
+pref(P,X) :-
+    nb_current(P,_),
+    nb_getval(P,Y),
+    ( Y = X
+    ;    ( Y = nie(Z), Z \= X)),
+    !.
+
+pref(P,X) :-
+    format("~w:\n", [P]),
+    read(Y),
+    nb_setval(P,Y),
+    (   Y = X
+    ;   ( Y = nie(Z), Z \= X)).
+
+
+termin(XS) :-
+    nb_current(termin,_),
+    nb_getval(termin,Y),
+    member(X,XS),
+    (   (Y1-Y2 = Y, X >= Y1, X =< Y2)
+    ;   (nie(Y1-Y2) = Y, (X < Y1 ; X > Y2))
+    ),
+    !.
+
+termin(XS) :-
+    format("termin (od-do):\n"),
+    read(Y),
+    nb_setval(termin,Y),
+    member(X,XS),
+    (   (Y1-Y2 = Y, X >= Y1, X =< Y2)
+    ;   (nie(Y1-Y2) = Y, (X < Y1 ; X > Y2))
+    ),
+    !.
+
+
+cena(X) :-
+    nb_current(cena,_),
+    nb_getval(cena,Y),
+    X=<Y.
+
+cena(X) :-
+    format("maksymalna cena:\n"),
+    read(Y),
+    nb_setval(cena, Y),
+    X =< Y.
+
+
+
+
+
+
+
+wakacje(zakopane) :-
+
+    pref(kraj,polska),
+    pref(teren,gory),
+    cena(2000).
+
+wakacje(hawaje) :-
+    termin([6,7,8]),
+    pref(kraj, usa),
+    pref(teren, morze),
+    cena(8000).
+
+
+
+
+
+
+
+
+
+clear :-
+    forall(member(A, [kraj,teren, termin, cena]), nb_delete(A)).
+
+wakacje2(X) :-
+    (   (wakacje(X), clear) ; (clear, fail)).
+
+
+
+
+
+
+