[AoC2022] Elisp 05-01

1 files changed, 50 insertions, 0 deletions

diff --git a/AoC2022/05/solver.el b/AoC2022/05/solver.el
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+++ b/AoC2022/05/solver.el
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+;;; solver.el --- Day 05 -*- lexical-binding: t; -*-
+;;
+;; Copyright (C) 2022 Óscar Nájera
+;;
+;; Author: Óscar Nájera <hi@oscarnajera.com>
+;; Maintainer: Óscar Nájera <hi@oscarnajera.com>
+;; Created: December 05, 2022
+;; Modified: December 05, 2022
+;;
+;; This file is not part of GNU Emacs.
+;;
+;;; Commentary:
+;;
+;;  Day 05
+;;
+;;; Code:
+(require 'subr-x)
+(defun solver-build-stacks ()
+  (let* ((stacks-len (length
+                      (split-string
+                       (buffer-substring-no-properties (line-beginning-position) (line-end-position)))))
+         (stacks (make-vector stacks-len nil))
+         next)
+    (message "%S" (list stacks-len (split-string
+                       (buffer-substring-no-properties (point) (line-end-position)))))
+
+    (while (setq next (search-backward "]" nil t))
+      (push (intern (string (char-before)))
+            (aref stacks (/ (- next (line-beginning-position) 1) 4))))
+    stacks))
+
+(defun solver-apply-moves (stacks)
+  (while (re-search-forward (rx bol "move " (group (+ digit)) " from " (group (+ digit)) " to " (group (+ digit))) nil t)
+    (let ((from (1- (string-to-number (match-string 2))))
+          (to (1- (string-to-number (match-string 3)))))
+      (dotimes (_ (string-to-number (match-string 1)))
+        (push (pop (aref stacks from)) (aref stacks to)))))
+  stacks)
+
+'(T P G V Q P F D H)
+(with-temp-buffer
+  (insert-file-contents "input")
+  (re-search-forward "^ 1")
+  (thread-last
+    (solver-build-stacks)
+    (solver-apply-moves)
+    (seq-map #'car)))
+
+(provide 'solver)
+;;; solver.el ends here