Advent of Code 2nd Puzzle

    (defn- load-code
      []
      (into [] (map #(-> %
                         (clojure.string/trim)
                         (Integer/parseInt))
                    (clojure.string/split (slurp "resources/puzzle2.txt") #","))))

    (defn- operation
      [operation-fn first-value second-value result-idx program-code]
      (swap!
       program-code
       #(assoc
         %
         result-idx
         (operation-fn first-value second-value))))

    (defn- addition
      [first-value second-value result-idx program-code]
      (operation + first-value second-value result-idx program-code))

    (defn- multiplication
      [first-value second-value result-idx program-code]
      (operation * first-value second-value result-idx program-code))

    (defn- calculate-output-for-noun-and-verb
      [noun verb]
      (let [program-code (atom (load-code))
            idx (atom 0)]
        (swap! program-code #(assoc % 1 noun 2 verb))
        (while (not= 99 (nth @program-code @idx))
          (let [operation (nth @program-code @idx)
                first-value (nth @program-code (nth @program-code (+ 1 @idx)))
                second-value (nth @program-code (nth @program-code (+ 2 @idx)))
                result-idx (nth @program-code (+ 3 @idx))]
             (cond
               (= operation 1) (addition first-value second-value result-idx program-code)
               (= operation 2) (multiplication first-value second-value result-idx program-code)))
          (swap! idx #(+ % 4)))
        (first @program-code)))

    (defn run-pt1
      []
      (prn (calculate-output-for-noun-and-verb 12 2)))

    (defn run-pt2
      []
      (loop [noun 99 verb 99]
        (cond
          (= noun -1)(throw (Exception. "Did not find a solution."))
          (= 19690720 (calculate-output-for-noun-and-verb noun verb)) (identity {:noun noun :verb verb})
          (= verb 0) (recur (dec noun) 99)
          :else (recur noun (dec verb)))))