interview

employees.clj

(defn load-employees-from-db []
  [{:name "Mary" :salary 6000}
   {:name "John" :salary 4000}])
 
(let [sum (atom 0)]
  (doseq [e (load-employees-from-db)]
    (reset! sum (+ @sum (:salary e))))
  (/ @sum
     (count (load-employees-from-db))))

snippet.clj

(first (map prn (vec (range 1024))))

sum_tree.clj

(defn sum-tree [root]
  (if (nil? root)
    nil
    (let [a-sum-tree (sum-tree (:left root))
          b-sum-tree (sum-tree (:right root))]
      (cond-> {:value (+ (:value root)
                         (or (:value a-sum-tree)
                             0)
                         (or (:value b-sum-tree)
                             0))}
        (some? a-sum-tree)
        (assoc :left a-sum-tree)

        (some? b-sum-tree)
        (assoc :right b-sum-tree)))))

(deftest test-sum-tree
  (is (= {:value 16,
          :left {:value 3
                 :left {:value 1}}
          :right {:value 12
                  :left {:value 4}
                  :right {:value 5}}}

         (sum-tree {:value 1
                    :left {:value 2
                           :left {:value 1}}
                    :right {:value 3
                            :left {:value 4}
                            :right {:value 5}}}))))

tree.txt

    1                  16
   / \                /  \
  2   3      ==>     3    12
 /   / \            /    /  \
1   4   5          1    4    5