diff --git a/maths/prime_factorization_fast.py b/maths/prime_factorization_fast.py
index 7b4af9885..6b1093bf4 100644
--- a/maths/prime_factorization_fast.py
+++ b/maths/prime_factorization_fast.py
@@ -1,7 +1,66 @@
 from __future__ import annotations
 from math import ceil, sqrt
+import time
 
+def timer(func):
+    def wrapper(*args, **kwargs):
+        start = time.time()
+        result = func(*args, **kwargs)
+        print(result)
+        end = time.time()
+        print(f"{func.__name__} took {end - start:.6f} seconds to execute.")
+        return result
+    return wrapper
 
+@timer
+def prime_factors(n: int) -> list[int]:
+    """
+    Returns prime factors of n as a list.
+
+    >>> prime_factors(0)
+    []
+    >>> prime_factors(100)
+    [2, 2, 5, 5]
+    >>> prime_factors(2560)
+    [2, 2, 2, 2, 2, 2, 2, 2, 2, 5]
+    >>> prime_factors(10**-2)
+    []
+    >>> prime_factors(0.02)
+    []
+    >>> x = prime_factors(10**241) # doctest: +NORMALIZE_WHITESPACE
+    >>> x == [2]*241 + [5]*241
+    True
+    >>> prime_factors(10**-354)
+    []
+    >>> prime_factors('hello')
+    Traceback (most recent call last):
+        ...
+    TypeError: '<=' not supported between instances of 'int' and 'str'
+    >>> prime_factors([1,2,'hello'])
+    Traceback (most recent call last):
+        ...
+    TypeError: '<=' not supported between instances of 'int' and 'list'
+
+    """
+    if not isinstance(n, int):
+        raise TypeError("Input must be an integer")
+
+    if n <= 0:
+        return []
+
+    i = 2
+    factors = []
+    while i * i <= n:
+        if n % i:
+            i += 1
+        else:
+            n //= i
+            factors.append(i)
+    if n > 1:
+        factors.append(n)
+    return factors
+
+@timer
 def primeproduct(num: int) -> list[int]:
     """
     >>> primeproduct(868)
@@ -14,6 +73,8 @@ def primeproduct(num: int) -> list[int]:
     >>> primeproduct(-2342)
     []
     """
+    if not isinstance(num, int):
+        raise TypeError("Input must be an integer")
 
     if num <= 1:
         return []
@@ -22,7 +83,6 @@ def primeproduct(num: int) -> list[int]:
     while num > 1:
         if len(prime_factors) >= 1 and prime_factors[-1] % num == 0:
             prime_factors.append(prime_factors[-1])
-
         else:
             sq = ceil(sqrt(num))
             flag = 0
@@ -34,28 +94,23 @@ def primeproduct(num: int) -> list[int]:
                         prime_factors.append(i)
                         flag = 1
                         break
-
             else:
                 while num % 2 == 0:
                     num = num // 2
                     prime_factors.append(2)
-
                 for i in range(3, sq + 1, 2):
                     if num % i == 0:
                         num = num // i
                         prime_factors.append(i)
                         flag = 1
                         break
-
             if not flag and num > 1:
                 prime_factors.append(num)
                 num = 1
                 break
-
     return prime_factors
 
-
 if __name__ == "__main__":
-    import doctest
-
-    doctest.testmod()
+    n = int(input('enter number: ').strip())
+    primeproduct(n)
+    prime_factors(n)