% 50
domains
int = integer
list=int*

predicates
nondeterm enter(list)
nondeterm run
nondeterm do(char)
nondeterm sublist(list,int,int,list)

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

sublist([X|_],1,1,[X]).
sublist([],_,_,[]).
sublist([X|Xs],1,K,[X|Ys]):-
       K>1,
       K1 = K-1,
       sublist(Xs,1,K1,Ys).
sublist([_|Xs],I,K,Ys):-
       I > 1,
       I1 = I-1,
       sublist(Xs,I1,K,Ys).

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 is ",L),nl,
write("Enter the constant "),readint(X),nl,
write("Enter the length "),readint(Y),nl,
sublist(L,X,Y,L1),nl,
write("New list is ",L1),nl.

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

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