2019.1.29 update more_fib

wingfish · wingfish · commit 7007d4d94290 · 2019-01-29T16:16:52.000+08:00
diff --git a/fib/fib.py b/fib/fib.py
@@ -17,18 +17,6 @@ def cache_fib(n, _cache={}):
     return n
 
 
-def pow_fib(n):
-    return pow(2 << n, n + 1, (4 << 2 * n) - (2 << n) - 1) % (2 << n)
-
-
-def ab_fib(n):
-    a, b = 1, 1
-    n = n-2
-    for i in range(n):
-        a, b = b, a+b
-    return b
-
-
 if __name__ == "__main__":
     x = 47
     start = time.time()
diff --git a/fib/more_fib.py b/fib/more_fib.py
@@ -0,0 +1,33 @@
+import time
+
+
+def pow_fib(n):
+    return pow(2 << n, n + 1, (4 << 2 * n) - (2 << n) - 1) % (2 << n)
+
+
+def for_fib(n):
+    a, b = 1, 1
+    n = n-2
+    for i in range(n):
+        a, b = b, a+b
+    return b
+
+
+def list_fib(n):
+
+    list_f = []
+    f = 1
+    list_f.append(f)
+    list_f.append(f)  # because the fibonacci sequence has two 1's at first
+    for i in range(n-2):
+        f = list_f[-1] + list_f[-2]  # says that f = the sum of the last two f's in the series
+        list_f.append(f)
+    return f
+
+
+if __name__ == "__main__":
+    x = 47
+    start = time.time()
+    res = list_fib(x)
+    elapsed = time.time() - start
+    print("Python Computed fib(%s)=%s in %0.8f seconds" % (x, res, elapsed))
