[AoC2022] ELisp 10-1

1 files changed, 49 insertions, 0 deletions

diff --git a/AoC2022/10/solver.el b/AoC2022/10/solver.el
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+;;; solver.el --- Day 10 -*- lexical-binding: t; -*-
+;;
+;; Copyright (C) 2022 Óscar Nájera
+;;
+;; Author: Óscar Nájera <hi@oscarnajera.com>
+;; Maintainer: Óscar Nájera <hi@oscarnajera.com>
+;; Created: December 10, 2022
+;; Modified: December 10, 2022
+;;
+;; This file is not part of GNU Emacs.
+;;
+;;; Commentary:
+;;
+;;  Day 10
+;;
+;;; Code:
+
+(require 'f)
+(require 'subr-x)
+(require 'cl-lib)
+(require 'ert)
+
+(defsubst solver-probe (cycle register)
+  (when (memq cycle '(20 60 100 140 180 220))
+    (* cycle register)))
+
+(let ((register 1)
+      (cycle 1)
+      measures)
+  (dolist (instruction (split-string (f-read "input") "\n"))
+    (cl-incf cycle)
+    (let ((step1 (solver-probe cycle register)) ;; the noop default
+          (step2                                ;; addx takes 2 cycles
+           (when (string-prefix-p "addx" instruction)
+             (cl-incf cycle)
+             (cl-incf register (string-to-number (cadr (split-string instruction))))
+             (solver-probe cycle register))))
+      (when-let ((probe (or step1 step2)))
+        (push probe measures))))
+  (list (reverse measures)
+        (apply #'+ measures)
+        cycle))
+
+
+
+
+
+(provide 'solver)
+;;; solver.el ends here