ExercitiiPLRaduP

% Lists

member_of(X,[X|_]).
member_of(X,[_|Tail]) :- member_of(X,Tail).

concat_lists([], List, List).
concat_lists([Elem | List1], List2, [Elem | List3]) :-
        concat_lists(List1, List2, List3).

nr_elem([], 0).
nr_elem([H|T], N) :- nr_elem(T, M), N is M + 1.

schimba([], []).
schimba([H | T], [H2 | T2]) :- H2 is H*2, schimba(T, T2).

prefix(P, L) :- append(P,_,L).
sufix(S, L) :- append(_,S,L).

all_a([]).
all_a([a|T]) :- all_a(T).

trans_a_b([], []).

trans_a_b([a | T], [ b | B]) :- trans_a_b(T, B).

scalarMult(S, [], []).
scalarMult(S, [H | T], [H2 | T2]) :- H2 is S * H, scalarMult(S, T, T2).

dot([], [], 0).
dot([H1 | T1], [H2 | T2], R) :- dot(T1, T2, R2), R is R2 + H1 * H2.

max([X] , X).
max([H | T], H) :- max(T, M), H >= M.
max([H | T], M) :- max(T, M), H < M.

palindrome([]).
palindrome(L) :- inversa_aux(L, [], L).

inversa([],[]).
inversa([H|T], I):- inversa(T, I1), append(I1, [H], I).

inversa_aux([], A, A).
inversa_aux([H|T], R, A) :- inversa_aux(T, [H|R], A).

remove_duplicates([], []).
remove_duplicates([H | T], [H | R]) :- not(member(H, T)), remove_duplicates(T,R).
remove_duplicates([H | T], [R]):- member(H, T), remove_duplicates(T,R).
/** <examples>

?- member_of(a,[a,b,c]).
?- member_of(X,[a,b,c]).
?- concat_lists([1, 2, 3], [d, e, f, g], X).
?- concat_lists(X, Y, [a, b, c, d]).

*/