%35
domains
int = integer
list=int*

Predicates
nondeterm enter(list)
nondeterm run
nondeterm do(char)
nondeterm append(list, list, list)

clauses
enter([H|T]):-
write("Enter elements of the list or type 'end': "),
readint(H),
enter(T).
enter([]):-!.

append([], [], []):-!.
append([A], [B], [A,B]):-!.
append([A|T], [B|T2], [A, B|T1]):-
append(T, T2, T1).

run:-
write("*******ENTER*******"), nl,
write("- 1 to START"),nl,
write("- 0 to EXIT"),nl,
write("***********************"),nl,
write(">>"), readchar(X),
write(X), nl, do(X), run.

do('1'):-
enter(L),write("Your list 1 is ",L),nl,
enter(L1),write("Your list 2 is ",L1),nl,
append(L,L1,L2),nl,
write("New list is ",L2),nl.

do('0'):-
write("That's all"),exit.

do(_):-
write("Bad value"), nl.
goal
run.