aoc-day2.clj

(defn terp [mem ip]
  (let [[op a b o] (subvec mem ip)]
    (if (not= op 99)
      (recur
        (assoc mem o ((case op 1 + 2 *) (mem a) (mem b)))
        (+ ip 4))
      mem))))

(def mem (vec (read-string (str "[" (slurp "data/day2-input.txt") "]"))))

; part 1 (same as before)
(-> mem
    (assoc 1 12 2 2)
    (terp 0)
    (get 0))

; part 2
(first (for [noun (range 100), verb (range 100)
             :let [[p0] (terp (assoc mem 1 noun 2 verb) 0)]
             :when (= p0 19690720)]
         (+ (* 100 noun) verb))))