day02/intcode.clj

   1 (ns aoc.core
   2   [:require [clojure.string :as str]])
   3
   4 (def get-list-from-file
   5   #(str/split #"," (slurp %)))
   6
   7 (def parse-int
   8   #(Integer/parseInt %))
   9
  10 (def opcodes {1 +, 2 *})
  11 (defn perform-operation [[opcode fst snd thd] program]
  12   (let [opcode-fn (opcodes opcode)
  13         fst-val (program fst)
  14         snd-val (program snd)]
  15     (assoc program thd (opcode-fn fst-val snd-val))))
  16
  17 (defn intcode [program]
  18   (loop [program program
  19          counter 0]
  20     (let [opcode (program counter)]
  21       (if (= opcode 99)
  22         program
  23         (recur (perform-operation (map program (take 4 (iterate inc counter)))
  24                                   program)
  25                (+ counter 4))))))
  26
  27 (defn -main []
  28   (let [input (mapv parse-int (get-list-from-file "input"))
  29         fixed-input (assoc input 1 12 2 1)]
  30     (println (first (intcode fixed-input)))))
  31
  32 (-main)