September Morn Update

Task/Fibonacci-sequence/Clojure/fibonacci-sequence-10.clj

@@ -0,0 +1,16 @@
+(ns fib.core)
+(require '[clojure.core.async
+           :refer [<! >! >!! <!! timeout chan alt! go]])
+
+(defn fib [c]
+  (loop [a 0 b 1]
+    (>!! c a)
+    (recur b (+ a b))))
+
+
+(defn -main []
+  (let [c (chan)]
+    (go (fib c))
+    (dorun
+      (for [i (range 10)]
+        (println (<!! c))))))

Task/Fibonacci-sequence/Clojure/fibonacci-sequence-7.clj

@@ -1,6 +1,11 @@
 (defn fib [n]
-  (case n
-    0 0
-    1 1
-    (+ (fib (- n 1))
-       (fib (- n 2)))))
+  (letfn [(fib* [n]
+            (if (zero? n)
+              [0 1]
+              (let [[a b] (fib* (quot n 2))
+                    c (*' a (-' (*' 2 b) a))
+                    d (+' (*' b b) (*' a a))]
+                (if (even? n)
+                  [c d]
+                  [d (+' c d)]))))]
+    (first (fib* n))))

Task/Fibonacci-sequence/Clojure/fibonacci-sequence-8.clj

@@ -1,8 +1,6 @@
-(def fib
-  (memoize
-    (fn [n]
-      (case n
-        0 0
-        1 1
-        (+ (fib (- n 1))
-           (fib (- n 2)))))))
+(defn fib [n]
+  (case n
+    0 0
+    1 1
+    (+ (fib (- n 1))
+       (fib (- n 2)))))

Task/Fibonacci-sequence/Clojure/fibonacci-sequence-9.clj

@@ -1,16 +1,8 @@
-(ns fib.core)
-(require '[clojure.core.async
-           :refer [<! >! >!! <!! timeout chan alt! go]])
-
-(defn fib [c]
-  (loop [a 0 b 1]
-    (>!! c a)
-    (recur b (+ a b))))
-
-
-(defn -main []
-  (let [c (chan)]
-    (go (fib c))
-    (dorun
-      (for [i (range 10)]
-        (println (<!! c))))))
+(def fib
+  (memoize
+    (fn [n]
+      (case n
+        0 0
+        1 1
+        (+ (fib (- n 1))
+           (fib (- n 2)))))))