Advent of Code 2019

day1.clj

(require '[clojure.string :as str])

(def masses
  (map #(Integer/parseInt %)
       (str/split (slurp "input") #"\n")))

(defn elf-fuel [mass]
  (int (- (Math/floor (/ mass 3)) 2)))

(defn cumulative-elf-fuel [mass]
  (if (pos? (elf-fuel mass))
    (+ (elf-fuel mass) (cumulative-elf-fuel (elf-fuel mass)))
    0))

(defn- applied-sum [f vals]
  (reduce + (map f vals)))

(defn part-one []
  (applied-sum elf-fuel masses))

(defn part-two []
  (applied-sum cumulative-elf-fuel masses))

(defn solve []
  (println (part-one))
  (println (part-two)))

(solve)