[AoC2022] Elisp 13

1 files changed, 55 insertions, 0 deletions

diff --git a/AoC2022/13/solver.el b/AoC2022/13/solver.el
new file mode 100644
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+++ b/AoC2022/13/solver.el
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+;;; solver.el --- DAy 13 -*- lexical-binding: t; -*-
+;;
+;; Copyright (C) 2022 Óscar Nájera
+;;
+;; Author: Óscar Nájera <hi@oscarnajera.com>
+;; Maintainer: Óscar Nájera <hi@oscarnajera.com>
+;; Created: December 13, 2022
+;; Modified: December 13, 2022
+;;
+;; This file is not part of GNU Emacs.
+;;
+;;; Commentary:
+;;
+;;  DAy 13
+;;
+;;; Code:
+
+(with-temp-buffer
+  (insert-file-contents "input")
+  (cl-loop
+   for i from 1
+   for a = (ignore-errors
+             (list
+              (json-parse-buffer :array-type 'list)
+              (json-parse-buffer :array-type 'list)))
+   while a
+   when (apply #'solver-compare a)
+   sum i
+   ;; when (= 84 i)
+   ;; do (apply #'solver-compare a)
+   ))
+
+(defun solver-compare (f s)
+  (cond
+   ((eq f s) 'next)
+   ((and (null f) (not (null s))) t)
+   ((and (not (null f)) (null s)) nil)
+   ((and (integerp f) (integerp s)) (< f s))
+   ((and (integerp f) (consp s)) (solver-compare (list f) s))
+   ((and (consp f) (integerp s)) (solver-compare f (list s)))
+   ((let ((result (solver-compare (car f) (car s))))
+      (if (eq result 'next) (solver-compare (cdr f) (cdr s))
+        result)))))
+
+(ert-deftest test-comparison ()
+  (pcase-dolist (`(,f ,s ,r)
+                 '((5 5 next)
+                   (5 nil nil)
+                   (nil 5 t)
+                   (nil nil next)
+                   ('(9) '((8 7)) nil)
+                   ('(1 1 3 1 1) '(1 1 5 1 1) t)
+                   ('((1) (2 3 4)) '((1) 4) t)
+                   ('() '(5) t)))
+    (should (eq (solver-compare f s) r))))