Added factors.py

Author: VarunS2002

factors.py

@@ -0,0 +1,56 @@
+from typing import Optional
+
+
+class Factors:
+    @staticmethod
+    def factors_iteration(number: int, use_while: bool = False) -> list[int]:
+        factors: list[int] = []
+        negative_factors: bool = False
+        if number == 0:
+            raise ArithmeticError("Factors of zero don't exist.")
+        elif not isinstance(number, int):
+            raise ArithmeticError("Factors of non-integers is not supported.")
+        elif number < 0:
+            negative_factors = True
+        if use_while:
+            i: int = 1
+            while i < abs(number) + 1:
+                if abs(number) % i == 0:
+                    factors.append(i)
+                    if negative_factors:
+                        factors.append(-1 * i)
+                i += 1
+        else:
+            for i in range(1, abs(number) + 1):
+                if abs(number) % i == 0:
+                    factors.append(i)
+                    if negative_factors:
+                        factors.append(-1 * i)
+        return factors
+
+    @staticmethod
+    def factors_recursion(number: int, next_factor: Optional[int] = None, factors: Optional[list[int]] = None,
+                          negative_factors: bool = False) -> list[int]:
+        if next_factor is None and factors is None:
+            factors = []
+            next_factor = abs(number)
+            if number == 0:
+                raise ArithmeticError("Factors of zero don't exist.")
+            elif not isinstance(number, int):
+                raise ArithmeticError("Factors of non-integers is not supported.")
+            elif number < 0:
+                negative_factors = True
+        if next_factor == 0:
+            return list(reversed(factors))
+        elif abs(number) % next_factor == 0:
+            if negative_factors:
+                factors.append(-1 * next_factor)
+            factors.append(next_factor)
+        return Factors.factors_recursion(number, next_factor - 1, factors, negative_factors)
+
+
+if __name__ == '__main__':
+    input_number = int(input("Enter a non-zero integer: "))
+    print("Using iteration (for):", Factors.factors_iteration(input_number))
+    print("Using iteration (while):", Factors.factors_iteration(input_number, use_while=True))
+    print("Using recursion:", Factors.factors_recursion(input_number))