DouKaku?

-module(methinks_it_is_a_weasel).
-import(io).
-import(lists).
-import(random).
-export([start/0]).

get_char(CS) -> lists:nth(random:uniform(length(CS)),CS).

create(T,_,TS) when TS == 0 -> T;
create(T,CS,TS) -> create([get_char(CS)|T],CS,TS-1).
create(CS,TS) -> create("",CS,TS).

create_text_list(TL,_,_,S) when S == 0 -> TL;
create_text_list(TL,CS,TS,S) -> create_text_list([create(CS,TS)|TL],CS,TS,S-1).
create_text_list(CS,TS,S) -> create_text_list([],CS,TS,S).

rank(T,G) ->
    lists:foldl(
        fun({CT,CG},A) ->
            A +
            if
                CT == CG -> 1;
                true -> 0
            end
        end,
        0,
        lists:zip(T,G)
    ).

sort_text_list(TL,G) -> lists:sort(fun(A,B) -> rank(A,G) > rank(B,G) end,TL).

update_text(T,CS) ->
    P = random:uniform(length(T)),
    lists:append(lists:sublist(T,P-1),[get_char(CS)|lists:sublist(T,P+1,length(T)-P)]).

update_text_list(TL,G,CS,S,N) ->
    lists:sublist(
        sort_text_list(
            lists:foldl(
                fun(T,A) ->
                    lists:append(
                        A,
                        lists:map(
                            fun(_) ->
                                update_text(T,CS)
                            end,
                            lists:seq(1,N,1)
                        )
                    )
                end,
                [],
                TL
            ),
            G
        ),
        S
    ).

process([T|TL],G,CS,S,N,I) ->
    R = rank(T,G),
    L = length(G),
    if
        R == L ->
            io:format("goal(~w):~p~n",[I,T]);
        true ->
            io:format("process(~w):~p(~w)~n",[I,T,rank(T,G)]),
            process(update_text_list([T|TL],G,CS,S,N),G, CS, S, N, I+1)
    end.

start() ->
    G = "METHINKSITISAWEASEL",
    CS = lists:seq($A,$Z,1),
    S = 300,
    N = 5,
    process(sort_text_list(create_text_list(CS,length(G),S),G),G,CS,S,N,1).