Refactor for efficiency

src/project_euler_python/problems_001_050/Problem026.py

@@ -37,11 +37,17 @@ def compute():
 
     cycle_length = 0
     ans = 0
+    # Because denominators with factor 2 contribute only to the terminating
+    # part of a decimal. The repeating behavior comes from the part of the
+    # denominator that is coprime with 10, so evens are skipped
     for number in range(3, 1000, 2):
         if number % 5 == 0:
             continue
         p = 1
-        while 10**p % number != 1:
+        remainder = 10 % number
+        while remainder != 1:
+            # avoid huge exponentiation
+            remainder = (remainder * 10) % number
             p += 1
         if p > cycle_length:
             cycle_length, ans = p, number