src/tools/int_seq.py

@@ -1,20 +1,12 @@
-def factorial(n: int, start: int = 1) -> int:
+import math
+
+
+def factorial(n: int) -> int:
     """
     n! = 1 * 2 * 3 * 4 * ... * n
     1, 1, 2, 6, 24, 120, 720, ...
-
-    If you're looking for efficiency with start == 1, just use math.factorial(n)
-    which takes just 25% of the compute time on average, but this is the fastest
-    pure python implementation I could come up with and it allows for partial
-    multiplications, like 5 * 6 * 7 * 8 * .... * 17
     """
-    if start == n:
-        return n
-    if n - start == 1:
-        return n * start
-
-    middle = start + (n - start) // 2
-    return factorial(middle, start) * factorial(n, middle + 1)
+    return math.factorial(n)
 
 
 def fibonacci(n: int) -> int:
@@ -46,10 +38,3 @@ def pentagonal(n: int) -> int:
     0, 1, 5, 12, 22, 35, ...
     """
     return ((3 * n * n) - n) // 2
-
-
-def hexagonal(n: int) -> int:
-    if n == 1:
-        return 1
-
-    return n * 2 + (n - 1) * 2 + (n - 2) * 2 + hexagonal(n - 1)

src/tools/stopwatch.py

@@ -20,9 +20,7 @@ class StopWatch:
         self.stopped = perf_counter_ns()
         self.total_elapsed += self.elapsed()
 
-    def reset(self):
-        self.total_elapsed = 0
-        self.start()
+    reset = start
 
     def elapsed(self) -> int:
         if self.stopped is None: