AoC 2019, Day 5

day5.clj

(defn prefix-params [default params]
  (let [diff-ln (- (count default) (count params))]
    (if-not (== 0 diff-ln)
      (str (subs default 0 diff-ln) params)
      params)))

(defn read-instruction [s]
  (case s
    "1" [1 0 0 1]
    "2" [2 0 0 1]
    "3" [3 1]
    "4" [4 0]
    "7" [7 0 0 1]
    "8" [8 0 0 1]
    "99" [99]
    (let [[_ params s] (re-find #"([0-9]+)([0-9]{2})$" s)
          opcode (Integer/parseInt s)
          params (case opcode
                   1 (prefix-params "100" params)
                   2 (prefix-params "100" params)
                   5 (prefix-params "00" params)
                   6 (prefix-params "00" params)
                   7 (prefix-params "100" params)
                   8 (prefix-params "100" params)
                   params)
          params (->> (reverse params)
                      (mapv #(Character/digit ^char % 10)))]
      (into [opcode] params))))

(defn get-param [memory offset mode]
  (let [v (get memory offset)]
    (condp == mode
      0 (get memory v)
      1 v
      (throw (Error. (str "Unknown parameter mode " mode))))))

(defn read-params [memory offset params]
  (map-indexed #(get-param memory (+ %1 offset) %2) params))

(defn next-offset ^long [offset params]
  (+ offset (count params) 1))

(defn interpret [memory input]
  (let [memory (transient memory)]
    (loop [offset 0
           log (list)]
      (let [[opcode & raw-params] (read-instruction (str (get memory offset)))
            params (read-params memory (inc offset) raw-params)]
        (condp == opcode
          1 (let [[a b c] params]
              (assoc! memory c (+ a b))
              (recur (next-offset offset params) log))

          2 (let [[a b c] params]
              (assoc! memory c (* a b))
              (recur (next-offset offset params) log))

          3 (let [[a] params]
              (assoc! memory a input)
              (recur (next-offset offset params) log))

          4 (let [[a] params]
              (recur (next-offset offset params) (cons a log)))

          5 (let [[a b] params]
              (if-not (== 0 a)
                (recur b log)
                (recur (next-offset offset params) log)))

          6 (let [[a b] params]
              (if (== 0 a)
                (recur b log)
                (recur (next-offset offset params) log)))

          7 (let [[a b c] params]
              (if (< a b)
                (assoc! memory c 1)
                (assoc! memory c 0))
              (recur (next-offset offset params) log))

          8 (let [[a b c] params]
              (if (== a b)
                (assoc! memory c 1)
                (assoc! memory c 0))
              (recur (next-offset offset params) log))

          99 (when (every? zero? (rest log))
               (first log))

          (throw (Error. (str "Unknown opcode " opcode))))))))

(def input
  (->> (clojure.string/split (slurp "input_2019_5") #",")
       (map read-string)))

(defn input->memory [input]
  (->> input
       (map-indexed #(vector %1 %2))
       (into {})))

(def memory (input->memory input))

(comment
  (= 7265618 (interpret memory 1))
  (= 7731427 (interpret memory 5)))

input_2019_5

3,225,1,225,6,6,1100,1,238,225,104,0,1102,59,58,224,1001,224,-3422,224,4,224,102,8,223,223,101,3,224,224,1,224,223,223,1101,59,30,225,1101,53,84,224,101,-137,224,224,4,224,1002,223,8,223,101,3,224,224,1,223,224,223,1102,42,83,225,2,140,88,224,1001,224,-4891,224,4,224,1002,223,8,223,1001,224,5,224,1,223,224,223,1101,61,67,225,101,46,62,224,1001,224,-129,224,4,224,1002,223,8,223,101,5,224,224,1,223,224,223,1102,53,40,225,1001,35,35,224,1001,224,-94,224,4,224,102,8,223,223,101,6,224,224,1,223,224,223,1101,5,73,225,1002,191,52,224,1001,224,-1872,224,4,224,1002,223,8,223,1001,224,5,224,1,223,224,223,102,82,195,224,101,-738,224,224,4,224,1002,223,8,223,1001,224,2,224,1,224,223,223,1101,83,52,225,1101,36,77,225,1101,9,10,225,1,113,187,224,1001,224,-136,224,4,224,1002,223,8,223,101,2,224,224,1,224,223,223,4,223,99,0,0,0,677,0,0,0,0,0,0,0,0,0,0,0,1105,0,99999,1105,227,247,1105,1,99999,1005,227,99999,1005,0,256,1105,1,99999,1106,227,99999,1106,0,265,1105,1,99999,1006,0,99999,1006,227,274,1105,1,99999,1105,1,280,1105,1,99999,1,225,225,225,1101,294,0,0,105,1,0,1105,1,99999,1106,0,300,1105,1,99999,1,225,225,225,1101,314,0,0,106,0,0,1105,1,99999,1007,226,226,224,1002,223,2,223,1006,224,329,1001,223,1,223,1108,226,226,224,102,2,223,223,1006,224,344,101,1,223,223,1007,677,677,224,102,2,223,223,1006,224,359,101,1,223,223,1108,677,226,224,1002,223,2,223,1005,224,374,1001,223,1,223,7,677,226,224,102,2,223,223,1005,224,389,1001,223,1,223,1008,677,677,224,1002,223,2,223,1005,224,404,101,1,223,223,108,226,226,224,1002,223,2,223,1006,224,419,101,1,223,223,1008,226,677,224,1002,223,2,223,1006,224,434,1001,223,1,223,1107,677,226,224,1002,223,2,223,1005,224,449,101,1,223,223,1008,226,226,224,102,2,223,223,1005,224,464,1001,223,1,223,8,226,226,224,1002,223,2,223,1006,224,479,1001,223,1,223,107,226,677,224,102,2,223,223,1005,224,494,1001,223,1,223,7,226,226,224,102,2,223,223,1005,224,509,1001,223,1,223,107,226,226,224,102,2,223,223,1005,224,524,101,1,223,223,107,677,677,224,1002,223,2,223,1006,224,539,101,1,223,223,8,677,226,224,1002,223,2,223,1006,224,554,101,1,223,223,1107,677,677,224,1002,223,2,223,1005,224,569,101,1,223,223,108,226,677,224,1002,223,2,223,1006,224,584,101,1,223,223,7,226,677,224,1002,223,2,223,1005,224,599,1001,223,1,223,8,226,677,224,102,2,223,223,1006,224,614,1001,223,1,223,108,677,677,224,1002,223,2,223,1006,224,629,1001,223,1,223,1007,226,677,224,1002,223,2,223,1006,224,644,101,1,223,223,1108,226,677,224,102,2,223,223,1005,224,659,1001,223,1,223,1107,226,677,224,102,2,223,223,1006,224,674,1001,223,1,223,4,223,99,226