From c427a1fcacfe4e05275acc02971bb00eb7037058 Mon Sep 17 00:00:00 2001
From: Oscar Najera <hi@oscarnajera.com>
Date: Thu, 14 Dec 2023 10:47:00 +0100
Subject: part 2, off by one error
---
AoC2023/day11/solver.lisp | 27 ++++++++++++++++-----------
1 file changed, 16 insertions(+), 11 deletions(-)
(limited to 'AoC2023')
diff --git a/AoC2023/day11/solver.lisp b/AoC2023/day11/solver.lisp
index e7feabf..666b71c 100644
--- a/AoC2023/day11/solver.lisp
+++ b/AoC2023/day11/solver.lisp
@@ -1,6 +1,7 @@
;; 9:59
;; 10:31 part1
-;;
+;; 10:47 part2
+
(ql:quickload '(fiveam))
(defparameter eg-input "...#......
.......#..
@@ -20,16 +21,16 @@
(defun shift (coord spacers)
(count-if (lambda (idx) (< idx coord)) spacers))
-(defun expanded (point free-rows free-cols)
+(defun expanded (point free-rows free-cols multiplier)
(destructuring-bind (y x) point
- (list (+ y (shift y free-rows))
- (+ x (shift x free-cols)))))
+ (list (+ y (* multiplier (shift y free-rows)))
+ (+ x (* multiplier (shift x free-cols))))))
(fiveam:test parts
(fiveam:is (= 1 (shift 5 '(3 6))))
- (fiveam:is (equal '(7 4) (expanded '(5 3) '(1 2) '(2)))))
+ (fiveam:is (equal '(7 4) (expanded '(5 3) '(1 2) '(2) 1))))
-(defun expanded-galaxies (rows)
+(defun expanded-galaxies (rows &optional (multiplier 1))
(let* ((free-rows (make-array (length rows) :initial-element t))
(free-cols (make-array (length (car rows)) :initial-element t))
(galaxies (loop for row in rows
@@ -45,7 +46,8 @@
(lambda (galaxie)
(expanded galaxie
(indexes free-rows)
- (indexes free-cols)))
+ (indexes free-cols)
+ multiplier))
galaxies)))
@@ -54,13 +56,16 @@
(+ (abs (- bx sx)) (abs (- by sy)))))
-(defun solver1 (rows)
- (loop with gals = (expanded-galaxies rows)
+(defun solver (rows &optional (multiplier 1))
+ (loop with gals = (expanded-galaxies rows multiplier)
for g across gals
for i from 0 sum
(loop for j from (1+ i) below (length gals)
sum (manhattan-dist g (aref gals j)))))
(fiveam:test solutions
- (fiveam:is (= 374 (solver1 (uiop:split-string eg-input :separator '(#\Newline)))))
- (fiveam:is (= 10154062 (solver1 (uiop:read-file-lines "input")))))
+ (fiveam:is (= 374 (solver (uiop:split-string eg-input :separator '(#\Newline)))))
+ (fiveam:is (= 1030 (solver (uiop:split-string eg-input :separator '(#\Newline)) 9)))
+ (fiveam:is (= 8410 (solver (uiop:split-string eg-input :separator '(#\Newline)) 99)))
+ (fiveam:is (= 10154062 (solver (uiop:read-file-lines "input"))))
+ (fiveam:is (= 553083047914 (solver (uiop:read-file-lines "input") 999999))))
--
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