remove_last(A, C) :-
    reverse(A, [_|B]),
    reverse(B, C).

strings_chars([], []).
strings_chars([A|As], [B|Bs]) :-
    string_chars(A, B),
    strings_chars(As, Bs).

read_file(Stream, []) :-
    at_end_of_stream(Stream).
read_file(Stream, [X|Xs]) :-
    \+ at_end_of_stream(Stream),
    read_line_to_codes(Stream, C),
    string_chars(S, C),
    split_string(S, "|", "", [A, B]),
    split_string(A, " ", "", A0),
    split_string(B, " ", "", [_|B0]),
    remove_last(A0, A1),
    strings_chars(A1, A2),
    strings_chars(B0, B1),
    X = [A2, B1],
    % X = S,
    read_file(Stream, Xs).

main :-
    open('../input/08', read, Stream),
    read_file(Stream, Lines), !,
    close(Stream),
    solve_all(Lines, Ans),
    count_all(Ans, S),
    print(S).

solve_all([], []).
solve_all([L|Ls], [A|As]) :-
    solve(L, A),
    solve_all(Ls, As).

should_count(1).
should_count(4).
should_count(7).
should_count(8).

count([], 0).
count([N|Ns], S) :-
    should_count(N),
    count(Ns, S1),
    S is S1 + 1.
count([N|Ns], S) :-
    \+ should_count(N),
    count(Ns, S).

count_all([], 0).
count_all([N|Ns], S) :-
    count(N, S0),
    count_all(Ns, S1),
    S is S0 + S1.

letter(a).
letter(b).
letter(c).
letter(d).
letter(e).
letter(f).
letter(g).

solve([Q, W], X) :-
    letter(A), letter(B), letter(C), letter(D), letter(E), letter(F), letter(G),
    A \= B, A \= C, A \= D, A \= E, A \= F, A \= G,
    B \= C, B \= D, B \= E, B \= F, B \= G,
    C \= D, C \= E, C \= F, C \= G,
    D \= E, D \= F, D \= G,
    E \= F, E \= G,
    F \= G,
    length(A1, 2), length(A7, 3), length(A4, 4), length(A8, 7),
    permutation([_, A1, _, _, A4, _, _, A7, A8, _], Q), !,
    decode_all(W, X, [A1, A4, A7, A8]).

decode_all([], [], _).
decode_all([Q|Qs], [W|Ws], A) :-
    decode(Q, W, A),
    decode_all(Qs, Ws, A).

decode(Q, W, [A1, A4, A7, A8]) :-
    ((permutation(A1, Q), W is 1, !);
    (permutation(A4, Q), W is 4, !);
    (permutation(A7, Q), W is 7, !);
    (permutation(A8, Q), W is 8, !);
    (W is -1)).