happy holidays 2025

2025/.gitignore

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+input/
+.lein-repl-history
+*.iml

2025/project.clj

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+(defproject org.ajet/advent-of-code "0.0.0-SNAPSHOT"
+  :description "my 2024 advent of code solutions in clojure"
+  :url "http://github.com/ajetski/advent-of-code"
+  :min-lein-version "2.0.0"
+  :jvm-opts ["-Xmx16g"]
+  :plugins [[cider/cider-nrepl "0.57.0"]]
+  :dependencies [[org.clojure/clojure "1.12.0"]
+                 [org.clojure/data.priority-map "1.2.0"]
+                 [org.clojure/math.combinatorics "0.3.0"]
+                 [babashka/fs "0.5.23"]
+                 [org.babashka/http-client "0.4.22"]
+                 [org.clojure/core.match "1.1.0"]]
+  :source-paths ["src" "../shared/clj/src"])

2025/src/day01.clj

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+(ns day01
+  (:require input-manager
+            #_[clojure.string :as str]))
+
+(defn parse-line [line]
+  [(.charAt line 0)
+   (parse-long (.substring line 1))])
+
+(def input (->> (input-manager/get-input 2025 01)
+                (map parse-line)))
+
+(def op {\R +, \L -})
+
+(defn normalize [n]
+  (mod n 100))
+
+;; part 1
+(->> input
+     (reductions (fn [acc [dir turn-cnt]]
+                   (normalize ((op dir) acc turn-cnt)))
+                 50)
+     (filter (partial = 0))
+     count)
+
+;; part 2
+(->> input
+     (reduce (fn [[acc dial] [dir turn-cnt]]
+               (let [next-dial ((op dir) dial turn-cnt)]
+                 [(+ acc (cond (> next-dial 99) (int (/ next-dial 100))
+                               (< next-dial 0) (+ (abs (int (/ next-dial 100)))
+                                                  (if (= dial 0)
+                                                    0
+                                                    1))
+                               (= next-dial 0) 1
+                               :else 0))
+                  (normalize next-dial)]))
+             [0 50])
+     first)