advent of code day 16

adventofcode16.clj

(ns advent-of-code.day16)

(def input "11101000110010100")

(defn parse [input]
  (into [] (map #(if (= % \1) true false) input)))

; ppmap from brave clojure
(defn ppmap
  "Partitioned pmap, for grouping map ops together to make parallel
  overhead worthwhile"
  [grain-size f & colls]
  (apply concat
   (apply pmap
          (fn [& pgroups] (doall (apply map f pgroups)))
          (map (partial partition-all grain-size) colls))))

(defn expand [seed size]
  (if (< (count seed) size)
      (recur (into [] (concat seed [false] (ppmap 1000 not (rseq seed)))) size)
      (take size seed)))

(defn checksum [bools]
  (if (even? (count bools))
      (recur (into [] (ppmap 1000 #(= (first %) (second %)) (partition 2 bools))))
      bools))


(defn part1 []
  (count
    (checksum
      (expand (parse input) 272))))

(defn part2 []
  (checksum
    (expand (parse input) 35651584)))