Add 2023/06

src/2023/day06.lisp

@@ -0,0 +1,28 @@
+(defpackage :aoc/2023/06 #.cl-user::*aoc-use*)
+(in-package :aoc/2023/06)
+
+(defun parse-records (&optional (strings (uiop:read-file-lines #P"src/2023/day06.txt")))
+  (destructuring-bind (times records) strings
+    (mapcar #'list
+            (parse-positive-integers times)
+            (parse-positive-integers records))))
+
+(defun max-distance (time hold)
+  (* hold (- time hold)))
+
+(defun count-wins (input)
+  (destructuring-bind (time record) input
+    (looping
+      (dorangei (hold 0 time)
+        (count! (> (max-distance time hold) record))))))
+
+(defun massage-input (&optional (strings (uiop:read-file-lines #P"src/2023/day06.txt")))
+  (mapcar [remove-if-not #'digit-char-p _] strings))
+
+
+(define-solution (2023 06) (strings)
+  (values (reduce #'* (parse-records strings) :key #'count-wins)
+          (bnd1 (strings (massage-input strings))
+            (reduce #'* (parse-records strings) :key #'count-wins))))
+
+(define-test (2023 06) (220320 34454850))