Adopted new convention from template

src/Python/Problems001-050/Problem008.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python3
+#!/usr/bin/env python
 """
 Created on 28 Abr 2017
 
@@ -9,14 +9,29 @@ Solution for problem 8 of Project Euler
 https://projecteuler.net/problem=8
 """
 
+import collections
+from itertools import islice
+
 from utils import timeit
 
 
+# recipe from more-itertools
+def sliding_window(iterable, n):
+    # sliding_window('ABCDEFG', 4) -> ABCD BCDE CDEF DEFG
+    it = iter(iterable)
+    window = collections.deque(islice(it, n), maxlen=n)
+    if len(window) == n:
+        yield tuple(window)
+    for x in it:
+        window.append(x)
+        yield tuple(window)
+
+
 @timeit("Problem 8")
 def compute():
     """
     The four adjacent digits in the 1000-digit number that have the
-    greatest product are 9 × 9 × 8 × 9 = 5832.
+    greatest product are 9 x 9 x 8 x 9 = 5832.
 
             731671...963450
 
@@ -46,22 +61,18 @@ def compute():
         05886116467109405077541002256983155200055935729725
         71636269561882670428252483600823257530420752963450
         """
-    num = NUM.replace('\n', '').replace(' ', '')
+    num = NUM.replace("\n", "").replace(" ", "")
     adjacent_digits = 13
-    target = len(num) - adjacent_digits #- 1
-    ans, i = 0, 0
-    while i < target:
-        a, j = 1, i
-        while j < (i + adjacent_digits):
-            a = a * int(num[j])
-            j += 1
-        if a > ans:
-            ans = a
-        i += 1
+    ans = 0
+    for nums in sliding_window(num, adjacent_digits):
+        prod = 1
+        for num in nums:
+            prod *= int(num)
+        if prod > ans:
+            ans = prod
 
     return ans
 
 
 if __name__ == "__main__":
-
-    print(f"Result for Problem 8: {compute()}")
+    print(f"Result for Problem 8 is {compute()}")