Add homework 6 solutions

fedorind.pl

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+% Here are a bunch of facts describing the Simpson's family tree.
+% Don't change them!
+
+female(mona).
+female(jackie).
+female(marge).
+female(patty).
+female(selma).
+female(lisa).
+female(maggie).
+female(ling).
+
+male(abe).
+male(clancy).
+male(herb).
+male(homer).
+male(bart).
+
+married_(abe,mona).
+married_(clancy,jackie).
+married_(homer,marge).
+
+married(X,Y) :- married_(X,Y).
+married(X,Y) :- married_(Y,X).
+
+parent(abe,herb).
+parent(abe,homer).
+parent(mona,homer).
+
+parent(clancy,marge).
+parent(jackie,marge).
+parent(clancy,patty).
+parent(jackie,patty).
+parent(clancy,selma).
+parent(jackie,selma).
+
+parent(homer,bart).
+parent(marge,bart).
+parent(homer,lisa).
+parent(marge,lisa).
+parent(homer,maggie).
+parent(marge,maggie).
+
+parent(selma,ling).
+
+
+
+%%
+% Part 1. Family relations
+%%
+
+% 1. Define a predicate `child/2` that inverts the parent relationship.
+child(X, Y) :- parent(Y, X).
+
+% 2. Define two predicates `isMother/1` and `isFather/1`.
+isMother(X) :- female(X), parent(X, _).
+isFather(X) :- male(X), parent(X, _).
+
+% 3. Define a predicate `grandparent/2`.
+grandparent(X, Y) :- parent(X, Z), parent(Z, Y).
+
+% 4. Define a predicate `sibling/2`. Siblings share at least one parent.
+sibling(X, Y) :- parent(Z, X), parent(Z, Y), X \= Y.
+
+% 5. Define two predicates `brother/2` and `sister/2`.
+brother(X, Y) :- sibling(X, Y), male(X).
+sister(X, Y) :- sibling(X, Y), female(X).
+
+% 6. Define a predicate `siblingInLaw/2`. A sibling-in-law is either married to
+%    a sibling or the sibling of a spouse.
+siblingInLaw(X, Y) :- married(X, SB), sibling(SB, Y) ; married(Y, SP), sibling(X, SP).
+
+% 7. Define two predicates `aunt/2` and `uncle/2`. Your definitions of these
+%    predicates should include aunts and uncles by marriage.
+aunt(X, Y) :- child(Y, P), (siblingInLaw(X, P) ; sibling(X, P)), female(X).
+uncle(X, Y) :- child(Y, P), (siblingInLaw(X, P) ; sibling(X, P)), male(X).
+
+% 8. Define the predicate `cousin/2`.
+cousin(X, Y) :- parent(P1, X), parent(P2, Y), siblingInLaw(P1, P2).
+
+% 9. Define the predicate `ancestor/2`.
+ancestor(X, Y) :- parent(X, Y) ; parent(P, Y), ancestor(X, P).
+
+% Extra credit: Define the predicate `related/2`.
+% TODO
+related(X, X, _).
+related(X, Y, V) :- not(member(Y, V)),
+    (child(Y, S), related(X, S, [Y|V]) ;
+     parent(Y, C), related(X, C, [Y|V]) ;
+     married(Y, S), related(X, S, [Y|V])).
+related(X, Y) :- related(X, Y, []), X \= Y.
+
+%%
+% Part 2. Language implementation (see course web page)
+%%
+cmd(X) :- number(X).
+cmd(X) :- string(X).
+cmd(X) :- bool(X).
+cmd(add).
+cmd(lte).
+cmd(if(X, Y)).
+
+prog([X|T]) :- cmd(X), prog(T).
+prog([]).
+
+if(X, Y) :- prog(X), prog(Y).
+
+bool(f).
+bool(t).
+
+cmd(X, OS, [X|OS]) :- prog(OS), (number(X) ; string(X) ; bool(X)).
+cmd(add, [X, Y | OS], [SUM| OS]) :- number(X), number(Y), is(SUM, X + Y).
+cmd(lte, [X, Y | OS], [t | OS]) :- number(X), number(Y), X =< Y.
+cmd(lte, [X, Y | OS], [f | OS]) :- number(X), number(Y), X > Y.
+cmd(if(P1, _), [t | OS], FS) :- prog(P1, OS, FS).
+cmd(if(_, P2), [f | OS], FS) :- prog(P2, OS, FS).
+
+prog([], S, S).
+prog([C|OP], S, FS) :- cmd(C), prog(OP), cmd(C, S, TS), prog(OP, TS, FS).