rendezvous with cassidoo challenge: 24.11.17

max_the_stock.clj

(ns max-the-stock
  (:require [clojure.test :refer [deftest is]]))

(defn max-the-stock [prices]
  (->> (rest prices)
       (reduce (fn [[min-price max-profit] price]
                 [(min min-price price)
                  (max max-profit (- price min-price))])
               [(first prices) 0])
       second))

(deftest max-the-stock-test
  (is (= (max-the-stock [7 1 5 3 6 4])
         5))

  (is (= (max-the-stock [7 6 4 3 1])
         0)))