feat: update structure

cs2104/labs/family.pl

@@ -0,0 +1,41 @@
+parent(a, b).
+parent(a, c).
+parent(b, d).
+parent(b, e).
+parent(c, f).
+parent(c, g).
+parent(f, h).
+parent(i,j).
+parent(f, i).
+
+ancestor(X, Y) :- parent(X, Y).
+ancestor(X, Y) :- parent(X, Z), ancestor(Z, Y).
+
+ancestor(a, X). 
+parent(a, ??)
+
+factorial(1, 1).
+factorial(N, F) :- N > 1, N1 is N - 1, factorial(N1, F1), F is F1 * N.
+
+faciter(1, Res, Res).
+faciter(N, Acc, Res) :- N > 1, N1 is N -1, Acc1 is N * Acc, faciter(N1, Acc1, Res).
+
+fib(0, 0).
+fib(1, 1).
+fib(N, F) :- N > 1, N1 is N-1, N2 is N-2, fib(N1, F1), fib(N2, F2), F is F1 + F2.
+
+fibiter(X, X, F1, F2, F1).
+fibiter(X, N, F1, F2, Result) :- X < N, X1 is X + 1, Aux is F1 + F2, fibiter(X1, N, F2, Aux, Result).
+
+head([H|_], H).
+tail([_|T], T).
+
+member(X, [X|_]).
+member(X, [_|T]) :- member(X, T).
+
+append([], L, L).
+append([H|T], L, [H|R]) :- append(T, L, R).
+
+reverse([], []).
+reverse([H|T], R) :- 
+  reverse(T, R1), append(R1, [H], R).