2024, day 2

Author: FelipeCortez

2024/02.clj

@@ -0,0 +1,22 @@
+(require '[clojure.string :as str])
+
+(defn valid-report? [xs]
+ (and (or (apply < xs) (apply > xs))
+ (every? (fn [[x y]] (<= 1 (abs (- x y)) 3))
+ (partition 2 1 xs))))
+
+(defn dampen-problems
+ ([xs]
+ (cons xs (dampen-problems [] xs)))
+ ([before [head & tail]]
+ (if (seq tail)
+ (lazy-seq (cons (into before tail)
+ (dampen-problems (conj before head) tail)))
+ [before])))
+
+(let [reports
+ (->> (slurp "2024/02.in")
+ (str/split-lines)
+ (map (fn [line] (map parse-long (re-seq #"\d+" line)))))]
+ [(count (filter valid-report? reports))
+ (count (filter #(some valid-report? (dampen-problems %)) reports))])