prolog kol1

% Duplicate elements in list %

dupl([], []).

dupl([G | R], [G | [G | Res]]):-
    dupl(R, Res).

% --------------------------- %

% Duplicate n times elements in list %
dupln(L, N, R):-
  duplin(L, N, R, N).

duplin([], _, [], _).

duplin([G | R], N, L, 0):-
	duplin(R, N, L, N).
	
duplin([G | R], N, [G | R1], N1):-
	N2 is N1 - 1,
	duplin([G | R], N, R1, N2).

% ------------------------------------ %

% Drop every N'th element from a list %

drop(L, N, R):-
	drop(L, N, R, N).

drop([], _, [], _).
drop([G | R], N, R1, 1):-
	drop(R, N, R1, N).
drop([G | R], N, [G | R1], N1):-
	N1 > 1,
	N2 is N1 - 1,
	drop(R, N, R1, N2).

% ------------------------------------ %

% Split elements in list by a given number %

split([], _, [], []).
split([G | R], 0, L1, [G | R1]):-
	split(R, 0, L1, R1).
split([G | R], N, [G | R1], L2):-
	N > 0,
	N1 is N - 1,

	split(R, N1, R1, L2).

% ---------------------------------------- %

% Slice elements from list %


slice([G | _], 1, 1, [G]).

slice([G | R], 1, E, [G | R1]):-
	E1 is E - 1,
	slice(R, 1, E1, R1).

slice([ G | R], B, E, L1):-
	B1 is B - 1,
	E1 is E - 1,
	slice(R, B1, E1, L1).

% ------------------------ %


% Remove k-th element from list %

remove([G | R], 1, R, G).
remove([G | R], K, [G | R1], N):-
	K1 is K - 1,
	remove(R, K1, R1, N).

% ----------------------------- %

% Insert element at n-th position on list %

insert(El, L, 1, [El | L]).
insert(El, [G | R], P, [G | Res]):-
	P1 is P - 1,
	insert(El, R, P1, Res).

% --------------------------------- %

% Create list with numbers in given range %


range(X, X, [X]).
range(X, Y, [X | R1]):-
	X1 is X + 1,
	range(X1, Y, R1).

% --------------------------------------- %

% Find n-th element of list %

nth([G | _], 1, G).
nth([G | R], N, E):-
	N1 is N - 1,
	nth(R, N1, E).

% ----------------------------------------- %

% ------------------------ KOLOKVIJ ZADACI -------------------------- %

% Zadatak 1 %
pomnozi([], _, []).
pomnozi([G | R], P, Res):-
	pomnozi(R, P, Res1),
	Result is G * P,
	Res = [Result | Res1].
	
% Zadatak 2 %
zbroji_l([], [], []).
zbroji_l([G | R], [G1 | R1], Res):-
	zbroji_l(R, R1, L3),
	Re is G + G1,
	Res = [Re | L3].

% Zadatak 3 %
manji_od([], _, []).
manji_od([G | R], N, Res):-
	manji_od(R, N, Res1),
	(
	 G < N
	-> Res = [G | Res1]
	;
	 Res = Res1
	 ).

% Zadatak 4 %
dan(pon, 1).
dan(uto, 2).
dan(sri, 3).
dan(cet, 4).
dan(pet, 5).
dan(sub, 6).
dan(ned, 7).

dan_u_tjednu(Dan, Broj):-
	dan(Dan, Broj).

% Zadatak 5 %
podlista(L1, L2):-
	podlista(L1, L2, L1).

podlista([], L, _).
podlista([G | R], [G1 | R1], Tmp):-
	podlista(Tmp, R1, Tmp).
podlista([G | R], [G | R1], Tmp):-
	podlista(R, R1, Tmp).



% Or this solution -> don't work for every case %
podlista_second([], _).
podlista_second([G | R], [G | R1]):-
	podlista(R, R1).

% Zadatak 6 %
pomnozi([X], X).
pomnozi([G | R], Res):-
	integer(G),
	pomnozi(R, Res1),
	Res is G * Res1.

:- op(600, xfx, voli).

% Zadatak 7 %
ivek voli barica.
barica voli joza.
barica voli ivek.
joza voli stefica.
stefica voli joza.

ljubavni_par( X, Y ) :-
	X voli Y,
	Y voli X.

parovi(L):-
	setof(par(X, Y), X voli Y, L).

% Zadatak 8 %

% Predicate for substraction %
oduzmi([A, B, C, D, E], [F, G, H, I, J], [R1, R2, R3, R4, R5]):-
	R1 is A - F,
	R2 is B - G,
	R3 is C - H,
	R4 is D - I,
	R5 is E - J.

% Operator for substraction %
:- op(600, xfx, vminus).
:- op(700, xfx, vjednako).

[A, B, C, D, E] vminus [F, G, H, I, J] vjednako [R1, R2, R3, R4, R5]:-
	R1 is A - F,
	R2 is B - G,
	R3 is C - H,
	R4 is D - I,
	R5 is E - J.

% Zadatak 9 %
:- op(600, xfx, mputa).
:- op(700, xfx, mjednako).

[[X1, X2], [X3, X4]] mputa [[Y1, Y2], [Y3, Y4]] mjednako[[R1, R2], [R3, R4]]:-
	R1 is (X1 * Y1) + (X2 * Y3),
	R2 is (X1 * Y2) + (X2 * Y4),
	R3 is (X3 * Y1) + (X4 * Y3),
	R4 is (X3 * Y2) + (X4 * Y4).

mputa([[X1, Y1], [X2, Y2]], [[X3, Y3], [X4, Y4]], [[R1, R2], [R3, R4]]):-
	R1 is (X1 * Y1) + (X2 * Y3),
	R2 is (X1 * Y2) + (X2 * Y4),
	R3 is (X3 * Y1) + (X4 * Y3),
	R4 is (X3 * Y2) + (X4 * Y4).

% Zadatak 10 %
:- op(600, xfx, +++).
:- op(700, xfx, ===).

[] +++ L2 === L2.
[G | R] +++ L2 === [G | Tmp]:-
	R +++ L2 === Tmp.

% Zadatak 11 %
rodjen( ivek, 1986 ).
rodjen( joza, 1989 ).
rodjen( bara, 1990 ).
rodjen( stef, 1977 ).

god_rac(C, G, R):-
	rodjen(C, T),
	R is G - T.

starosti(L, G):-
	bagof((star(X, Y)), god_rac(X, G, Y), L).

% Zadatak 12 %
code([], []).
code([G | R], Res):-
	code(R, Res1),
	Crypt is G + 1,
	%char_code(Letter, Crypt),
	Res = [Crypt | Res1].
	
kodiraj(I, Res):-
	I = L,
	code(L, Tmp),
	%concat_atom(Tmp, Res).
	codes_to_term(Tmp, Res).

% ----------------------------------------------------------------- %