24/3 in clj

clojure/y2024/d03.bb

@@ -0,0 +1,43 @@
+#!/usr/bin/env bb
+
+(ns y2024.d03
+  (:require [babashka.cli :as cli]))
+
+
+(def cli-options {:input {:default "../../inputs/2024/03.input" :type :string}})
+
+(def opts (cli/parse-opts *command-line-args* {:spec cli-options}))
+
+(def input
+  (->> (slurp (get opts :input))))
+
+(defn solve [data part2?]
+  (let [re #"mul\((\d+),(\d+)\)|do\(\)|don't\(\)"]
+    (loop [matches (re-seq re data)
+           result 0
+           doing? true]
+      (if (empty? matches)
+        result
+        (let [[match & rst] (first matches)
+              [res do?]
+              (cond
+                (= match "do()") [result true]
+                (= match "don't()") [result false]
+
+                (or doing?  (not part2?))
+                (let [[a b] (map parse-long rst)]
+                  [(+ result (* a b)) doing?])
+
+                :else
+                [result doing?])]
+          (recur (rest matches) res do?))))))
+
+(defn part1 [data]
+  (solve data false))
+
+
+(defn part2 [data]
+  (solve data true))
+
+(prn {:part1 (part1 input)
+      :part2 (part2 input)})