Data commit

Task/Josephus-problem/Clojure/josephus-problem.clj

@@ -0,0 +1,13 @@
+(defn rotate [n s] (lazy-cat (drop n s) (take n s)))
+
+(defn josephus [n k]
+   (letfn [(survivor [[ h & r :as l] k]
+             (cond (empty? r) h
+                   :else      (survivor (rest (rotate (dec k) l)) k)))]
+     (survivor (range n) k)))
+
+(let [n 41 k 3]
+   (println (str "Given " n " prisoners in a circle numbered 1.." n
+                 ", an executioner moving around the"))
+   (println (str "circle " k " at a time will leave prisoner number "
+                 (inc (josephus n k)) " as the last survivor.")))