Advent of Code 2018 day 01

AoC2018-day-01.clj

(defn get-final-freq
  "Day one: calculate resulting frequency"
  [freq_list]
  ; 1. clojurist prefer to use `-` instead of `_` in names
  ; 2. I'm not sure how you got and what's inside `freq_list` (I suppose integers, then it's fine)
  (reduce + freq_list))

(defn repeated-freq
  "Day one: first occur of repeated frequency"
  [freq_list]
  (reduce
    (fn [vect freq]
      ; 3. I don't like the name `vect` (clojurist would use `col`), but in this context it's
      ;    something like `seen`
      (let [curr_freq (+ (last vect) freq)
            new_vect (conj vect curr_freq)
            ; 4. I don't like the name `new_vect`, for me it's `frequencies` (BTW take a look at
            ;    reductions function in core - does the same thing but lazily)
            ]
        (if (some #(= curr_freq %) vect)
          ; 5. This is the place where I would start to think about better data structure,
          ;    overall idea is good, but the complexity of this algo is not - could be
          ;    better if you used set
          (reduced (last new_vect))
          ; 6. Two times calling `last` on vector has speed consequencies (small detail, I know, who cares)
          new_vect)))
    [0]
    (cycle freq_list)))