diff options
Diffstat (limited to 'AoC2022/15')
| -rw-r--r-- | AoC2022/15/solver.lisp | 61 |
1 files changed, 45 insertions, 16 deletions
diff --git a/AoC2022/15/solver.lisp b/AoC2022/15/solver.lisp index 3d4fafd..0166b23 100644 --- a/AoC2022/15/solver.lisp +++ b/AoC2022/15/solver.lisp @@ -1,13 +1,6 @@ (ql:quickload '(fiveam str cl-ppcre arrows uiop)) -(setf markers - (loop for line in (uiop:read-file-lines "eg-in") - for (sx sy bx by) = (multiple-value-bind (match values) - (cl-ppcre:scan-to-strings "Sensor at x=(-?\\d+), y=\(-?\\d+\): closest beacon is at x=(-?\\d+), y=(-?\\d+)" - line) - (map 'list #'parse-integer values)) - nconc (list (cons sx sy) (cons bx by)))) (defun bounds (markers) (list (list @@ -28,6 +21,13 @@ (when (and (<= xmin x xmax) (<= ymin y ymax)) (+ (- x xmin) (* (- y ymin) stride))))))) +(defun from-grid (bounds) + (destructuring-bind ((xmin xmax) (ymin _)) bounds + (declare (ignore _)) + (let ((stride (- xmax xmin -1))) + (lambda (pos) + (multiple-value-bind (y x) (floor pos stride) + (cons (+ x xmin) (+ y ymin))))))) (defun draw-grid (grid stride) (let ((out (make-string-output-stream))) @@ -37,17 +37,46 @@ (princ (case elt (0 ".") (1 "S") - (2 "B")) out))) + (2 "B") + (3 "#")) out))) (get-output-stream-string out))) -(let* ((bounds (bounds markers)) +(defun manhattan-dist (pos-sensor pos-beacon) + (destructuring-bind ((sx . sy) (bx . by)) (list pos-sensor pos-beacon) + (+ (abs (- bx sx)) (abs (- by sy))))) + +(defun markers (lines) + (loop for line in lines + for (sx sy bx by) = (multiple-value-bind (match values) + (cl-ppcre:scan-to-strings "Sensor at x=(-?\\d+), y=\(-?\\d+\): closest beacon is at x=(-?\\d+), y=(-?\\d+)" + line) + (declare (ignore match)) + (map 'list #'parse-integer values)) + nconc (list (cons sx sy) (cons bx by)))) + + +(let* ((lines (uiop:read-file-lines "eg-in")) + (markers (markers lines)) + (bounds (bounds markers)) (loc (in-grid bounds)) - (grid (grid bounds))) + (grid (grid bounds)) + (coords (from-grid bounds))) (loop for ((sx . sy) (bx . by)) on markers by #'cddr - do (progn (princ (list sx sy bx by)) - (setf (aref grid (funcall loc sx sy)) 1) + do (progn (setf (aref grid (funcall loc sx sy)) 1) (setf (aref grid (funcall loc bx by)) 2))) - (destructuring-bind ((xmin xmax) a) bounds - (princ (draw-grid grid (- xmax xmin -1))) - ) - ) + + (loop for (sensor beacon) on markers by #'cddr + for distance = (manhattan-dist sensor beacon) + do (loop + for elt across grid + and l from 0 + when (and (<= (manhattan-dist sensor (funcall coords l)) distance) (= elt 0)) + do (setf (aref grid l) 3))) + + (destructuring-bind ((xmin xmax) (ymin ymax)) bounds + (let ((stride (- xmax xmin -1))) + ;; (princ (draw-grid grid stride)) + (loop repeat stride + for l from (* (+ 10 ymin) stride) + when (= 3 (aref grid l)) + count it)))) |