From da1707b36559085b5ae660b2b250dbd56a909883 Mon Sep 17 00:00:00 2001
From: Dory <dory@dory.moe>
Date: Tue, 12 Dec 2023 11:50:35 -0800
Subject: [PATCH] d12p2. It was actually good; swipl's memoization table just
 didn't work.

---
 12/part1.pl       |  1 +
 12/part2.naive.pl | 63 ---------------------------------------------
 12/part2.pl       | 65 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 66 insertions(+), 63 deletions(-)
 delete mode 100644 12/part2.naive.pl
 create mode 100644 12/part2.pl

diff --git a/12/part1.pl b/12/part1.pl
index 16e6da2..9f89583 100644
--- a/12/part1.pl
+++ b/12/part1.pl
@@ -1,3 +1,4 @@
+% Usage: swipl part1.pl input.txt
 :- use_module(library(pio)).
 :- use_module(library(dcg/basics)).
 :- initialization(main, main).
diff --git a/12/part2.naive.pl b/12/part2.naive.pl
deleted file mode 100644
index f11f0af..0000000
--- a/12/part2.naive.pl
+++ /dev/null
@@ -1,63 +0,0 @@
-:- use_module(library(pio)).
-:- use_module(library(dcg/basics)).
-:- initialization(main, main).
-:- table nbads/2.
-:- table bads_or_unks/1.
-% :- table resolve/3.
-
-test :- main(['test.txt']).
-
-main([FileName | _]) :-
-    input(FileName, Lines),
-    % TrySolve = [Line-Bads, Prev, Curr]>>(
-    %     writef('%t, %t', [Line, Bads]),
-    %     resolve(Line, Bads, N),
-    %     Curr is Prev + N,
-    %     writef(' --> %t\n', [N])),
-    % foldl(TrySolve, Lines, 0, Ns),
-    TrySolve = [Line-Bads, N]>>(
-        resolve(Line, Bads, N), 
-        writef('%t <-- %t, %t\n', [N, Line, Bads])),
-    concurrent_maplist(TrySolve, Lines, Ns),
-    sum_list(Ns, Count),
-    writef('\nRes=%w, %w\n', [Ns, Count]).
-    
-% Bads is list of contiguous blocks of bad items in Xs; w/unks resolved in Y.
-resolve([], [], 1).
-resolve([good|Xs], Bads, Y) :- resolve(Xs, Bads, Y).
-resolve([unk|Xs], Bads, Y) :-
-    convlist({Xs, Bads}/[Choice, Yx]>>(resolve([Choice|Xs], Bads, Yx)),
-             [good, bad], Ys),
-    sum_list(Ys, Y).
-resolve([bad|Xs], [N|Bads], Y) :-
-    length(BadsUnks, N),
-    append(BadsUnks, [Next|RemainingXs], [bad|Xs]),
-    (Next = good; Next = unk),
-    bads_or_unks(BadsUnks),
-    resolve(RemainingXs, Bads, Y).
-
-% List contains all bads or unks
-bads_or_unks([]).
-bads_or_unks([bad|List]) :- bads_or_unks(List).
-bads_or_unks([unk|List]) :- bads_or_unks(List).
-    
-% List contains exactly N bad items.
-nbads([], 0).
-nbads([bad|List], N) :- N > 0, Remain is N - 1, nbads(List, Remain).
-
-% read input file into [(good;bad;unk)]-[list of bad runs]
-input(FileName, Lines) :- phrase_from_file(lines(Lines), FileName).
-
-lines([]) --> eos.
-lines([Status-Parity|Lines]) -->
-    (status(S), {append([S, [unk], S, [unk], S, [unk], S, [unk], S, [good]], Status)}),
-    (parity(P), {append([P, P, P, P, P], Parity)}),
-    lines(Lines).
-
-status([]) --> " ".
-status([good|Cdr]) --> ".", status(Cdr).
-status([bad|Cdr]) --> "#", status(Cdr).
-status([unk|Cdr]) --> "?", status(Cdr).
-
-parity([N]) --> number(N), ("\n"; eos).
-parity([N|Cdr]) --> number(N), ",", parity(Cdr).
diff --git a/12/part2.pl b/12/part2.pl
new file mode 100644
index 0000000..445f268
--- /dev/null
+++ b/12/part2.pl
@@ -0,0 +1,65 @@
+% Usage: swipl part2.pl input.txt
+:- use_module(library(pio)).
+:- use_module(library(dcg/basics)).
+:- initialization(main, main).
+
+test :- main(['test.txt']).
+
+main([FileName | _]) :-
+    input(FileName, Lines),
+    concurrent_maplist(resolve_repeated, Lines, Ns),
+    sum_list(Ns, Count),
+    writef('Res=%w\n', [Count]).
+    
+resolve_repeated(Line-Bads, N) :-
+    append([Line, [?], Line, [?], Line, [?], Line, [?], Line], L5),
+    append([Bads, Bads, Bads, Bads, Bads], B5),
+    abolish_private_tables, table(resolve/2),
+    resolve(L5-B5, N).
+
+% Bads is list of contiguous blocks of bad items in Xs; w/unks resolved in Y.
+resolve([]-[], 1).
+resolve([o|Xs]-Bads, Y) :- resolve(Xs-Bads, Y).
+resolve([?|Xs]-Bads, Y) :-
+    findall(N, (resolve([o|Xs]-Bads, N); resolve([#|Xs]-Bads, N)), Ys),
+    sum_list(Ys, Y).
+resolve([#|Xs]-[N|Bads], Y) :-
+    length(BadsUnks, N),
+    (   append(BadsUnks, [], [#|Xs]),
+        RemainingXs = []
+    ;   append(BadsUnks, [Next|RemainingXs], [#|Xs]), (Next = o; Next = ?)
+    ),
+    bads_or_unks(BadsUnks),
+    resolve(RemainingXs-Bads, Y).
+
+% List contains all bads or unks
+bads_or_unks([]).
+bads_or_unks([#|List]) :- bads_or_unks(List).
+bads_or_unks([?|List]) :- bads_or_unks(List).
+    
+% List contains exactly N bad items.
+nbads([], 0).
+nbads([#|List], N) :- N > 0, Remain is N - 1, nbads(List, Remain).
+
+processed_line(1, Line-Bads, NewLine-NewBads) :-
+    append(Line, [o], NewLine),
+    NewBads = Bads.
+
+% read input file into [(o;#;?)]-[list of bad runs]
+input(FileName, Lines) :- phrase_from_file(lines(Lines), FileName).
+
+lines([]) --> eos.
+lines([Status-Parity|Lines]) --> status(Status), parity(Parity), lines(Lines).
+
+status([]) --> " ".
+status([o]) --> all_dots, " ".
+status([o, #|Cdr]) --> all_dots, "#", status(Cdr).
+status([o, ?|Cdr]) --> all_dots, "?", status(Cdr).
+status([#|Cdr]) --> "#", status(Cdr).
+status([?|Cdr]) --> "?", status(Cdr).
+
+all_dots --> ".".
+all_dots --> ".", all_dots.
+
+parity([N]) --> number(N), ("\n"; eos).
+parity([N|Cdr]) --> number(N), ",", parity(Cdr).