TEKNILLINEN KORKEAKOULU

Tietojenkäsittelyopin laboratorio
Logiikkaohjelmointi Tik-76.144
SYKSY 1998

4. kotitehtävä

Henna Pietiläinen
Ti
45356D


4.a.

intersection([], X, []).

intersection([H|T], X, Intersection) :-
        member(H, X),
        member(H, Intersection),
        delete(Intersection, H, I2),
        intersection(T, X, I2).

intersection([H|T], X, Intersection) :-
        not(member(H, X)),
        not(member(H, Intersection)),
        intersection(T, X, Intersection).

member(H, [H|T]).
member(Z, [X|Y]) :-
        member(Z, Y).

delete([H|T], H, X) :-
        delete(T, H, X).

delete([H|T], Z, [X|Y]) :-
        H \== Z,
        delete(T, Z, Y).

delete([], X, []).

not(X) :- X, !, fail.
not(X).

4.b. 

tree_list(Tree, List) :-
        preorder(Tree, List).

preorder(tree(L, X, R), List) :-
        preorder(L, Lefts),
        preorder(R, Rights),
        append([X|Lefts], Rights, List).

preorder(0, []).

append([], Ylist, Ylist).
append([X|Xlist], Ylist, [X|Zlist]) :-
        append(Xlist, Ylist, Zlist).