advent-2024/p10/p10.org

Solution to p10

Load the file into a list of lines

(with-temp-buffer
     (insert-file-contents "input-test")
     (goto-char (point-min))
     (replace-regexp "^" "\"")
     (goto-char (point-min))
     (replace-regexp "$" "\"")
     (goto-char (point-min))
     (insert "(setq data '(")
     (goto-char (point-max))
     (insert "))")
     (eval-buffer))

and split into a list of list of chars

  (setq data-chars (-map (lambda (str) (--map (- (string-to-char it) ?0) (split-string str "\\|.+" t)))
			 data))

8	9	0	1	0	1	2	3
7	8	1	2	1	8	7	4
8	7	4	3	0	9	6	5
9	6	5	4	9	8	7	4
4	5	6	7	8	9	0	3
3	2	0	1	9	0	1	2
0	1	3	2	9	8	0	1
1	0	4	5	6	7	3	2

this yields the coordinates of the 0s

(-map #'cadr
	 (--filter (eq (car it) 0)
		   (-mapcat #'identity
			     (-map-indexed (lambda (y l) (-map-indexed (lambda (x el) (list el (list x y))) l)) data-chars))))

2	0
4	0
4	2
6	4
2	5
5	5
0	6
6	6
1	7