aoc2021-day03a Clojure/JVM program

; SPDX-License-Identifier: MIT
; Copyright (C) 2021 Tito Sacchi <tito@tilde.team>
; WARNING: These solutions were written while I was still learning Clojure and
; should by no means be taken as examples of good programming practice or fast
; implementations.

(ns aoc.2021.03a)

(defn parse-line [line] (map #(Integer/parseInt (str %)) line))

(defn update-counts [counts line]
  (->> line
       (parse-line)
       (map #(update %1 %2 inc) counts)))

(def most-common-bits
  (->> *in*
       (java.io.BufferedReader.)
       (line-seq)
       (reduce update-counts (repeat {0 0, 1 0}))
       (map #(key (apply max-key val %)))))

(defn from-bin [xs]
  (reduce
    #(case %2
       0 (* 2 %1)
       1 (inc (* 2 %1))) xs))

(def gamma (from-bin most-common-bits))
(def epsilon (from-bin (map #(- 1 %) most-common-bits)))
(println (* gamma epsilon))
    

NOTES:
Linux


Sun, 23 Jan 2022 12:49:47 GMT

COMMAND LINE:
clojure -cp /usr/share/java/data.priority-map.jar aoc2021_day03a.clj-1.clj 0 < aoc2021_day03a-input100000.txt

PROGRAM FAILED 


PROGRAM OUTPUT:

Execution error (StackOverflowError) at (REPL:1).
null

Full report at:
/tmp/clojure-2143501243086406022.edn