eungju

-module(p1_2).
-compile(export_all).

s([_]=L) ->
    [[L]];
s([A|L]) ->
    S = s(L),
    lists:append([lists:map(fun(X) -> [[A]|X] end, S)|lists:map(fun(X) -> each_append(A,X) end, S)]).

each_append(_, [], _, Acc) ->