AoC 2022 Day 7

.clj

(ns aoc2022.day7
  (:require
   [clojure.string :as str]
   [clojure.zip :as z]
   [clojure.core.match :refer [match]]))

(defn process-line
  [tree line]
  (match line
    ["$" "cd" ".."]
    (-> tree z/up)
    ["$" "cd" _]
    (-> (z/insert-child tree []) z/down)
    [(f-size :guard #(re-matches #"\d+" %)) _]
    (z/insert-child tree (parse-long f-size))
    :else
    tree))

;; Part 1
(->>
 (slurp "resources/input7.txt")
 str/split-lines
 (map #(str/split % #" "))
 (reduce process-line (z/vector-zip []))
 z/root
 (tree-seq vector? identity)
 (filter vector?)
 (map #(apply + (flatten %)))
 (filter #(<= % 100000))
 (apply +))

;; Part 2
(defn find-dir
  [[root & dirs]]
  (let [unused-space (- 70000000 root)
        required-space (- 30000000 unused-space)]
    (->>
     dirs
     reverse
     (drop-while #(< % required-space))
     first)))

(->>
 (slurp "resources/input7.txt")
 str/split-lines
 (map #(str/split % #" "))
 (reduce process-line (z/vector-zip []))
 z/root
 (tree-seq vector? identity)
 (filter vector?)
 (map #(apply + (flatten %)))
 (sort >)
 find-dir)