src/adventofcode2019/day06.clj

   1 (ns adventofcode2019.day06
   2     [:require [adventofcode2019.lib :refer :all]
   3               [clojure.string :as str]])
   4
   5 ;; FIXME: is the input guaranteed in-order?
   6 (defn a-orbits-b [orbits-map [b a]]
   7   (if (contains? orbits-map b)
   8     (-> (assoc orbits-map a {:parent b, :children [], :depth (inc (:depth b))})
   9         (update-in [b :children] conj a))
  10     (-> (assoc orbits-map b {:parent nil, :children [], :depth 0})
  11         (a-orbits-b [b a]))))
  12
  13 (defn day06 []
  14   (let [input (map #(str/split % #")") (get-list-from-file (input-file)))
  15         orbits-map (reduce a-orbits-b {} input)]
  16     (part1 (reduce + (map :depth orbits-map)))
  17     #_(part2)))