#### Max Product Subarray

R
```def max_product_subarray(numbers: list[int]) -> int:
"""
Returns the maximum product that can be obtained by multiplying a
contiguous subarray of the given integer list `nums`.

Example:
>>> max_product_subarray([2, 3, -2, 4])
6
>>> max_product_subarray((-2, 0, -1))
0
>>> max_product_subarray([2, 3, -2, 4, -1])
48
>>> max_product_subarray([-1])
-1
>>> max_product_subarray([0])
0
>>> max_product_subarray([])
0
>>> max_product_subarray("")
0
>>> max_product_subarray(None)
0
>>> max_product_subarray([2, 3, -2, 4.5, -1])
Traceback (most recent call last):
...
ValueError: numbers must be an iterable of integers
>>> max_product_subarray("ABC")
Traceback (most recent call last):
...
ValueError: numbers must be an iterable of integers
"""
if not numbers:
return 0

if not isinstance(numbers, (list, tuple)) or not all(
isinstance(number, int) for number in numbers
):
raise ValueError("numbers must be an iterable of integers")

max_till_now = min_till_now = max_prod = numbers[0]

for i in range(1, len(numbers)):
# update the maximum and minimum subarray products
number = numbers[i]
if number < 0:
max_till_now, min_till_now = min_till_now, max_till_now
max_till_now = max(number, max_till_now * number)
min_till_now = min(number, min_till_now * number)

# update the maximum product found till now
max_prod = max(max_prod, max_till_now)

return max_prod
```