%query: sublist(i,o). sublist(X,Y) :- append(U,X,V), append(V,W,Y). append([],Ys,Ys). append([X|Xs],Ys,[X|Zs]) :- append(Xs,Ys,Zs). /*TWDESC sub list with termination problem. */ /*TWDEMO selected_norms([listlength]). */ /*. */