Update sol1.py

Author: MaximSmolskiy

project_euler/problem_073/sol1.py

@@ -36,15 +36,14 @@ def solution(max_d: int = 12_000) -> int:
 
     fractions_number = 0
     for d in range(max_d + 1):
+        n_start = d // 3 + 1
+        n_step = 1
         if d % 2 == 0:
-            n_start = d // 3 + 2 if (d // 3 + 1) % 2 == 0 else d // 3 + 1
-            for n in range(n_start, (d + 1) // 2, 2):
-                if gcd(n, d) == 1:
-                    fractions_number += 1
-        else:
-            for n in range(d // 3 + 1, (d + 1) // 2):
-                if gcd(n, d) == 1:
-                    fractions_number += 1
+            n_start += 1 - n_start % 2
+            n_step = 2
+        for n in range(n_start, (d + 1) // 2, n_step):
+            if gcd(n, d) == 1:
+                fractions_number += 1
     return fractions_number