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"""
https://www.enjoyalgorithms.com/blog/median-of-two-sorted-arrays
"""


def find_median_sorted_arrays(nums1: list[int], nums2: list[int]) -> float:
"""
Find the median of two arrays.

Args:
nums1: The first array.
nums2: The second array.

Returns:
The median of the two arrays.

Examples:
>>> find_median_sorted_arrays([1, 3], [2])
2.0

>>> find_median_sorted_arrays([1, 2], [3, 4])
2.5

>>> find_median_sorted_arrays([0, 0], [0, 0])
0.0

>>> find_median_sorted_arrays([], [])
Traceback (most recent call last):
...
ValueError: Both input arrays are empty.

>>> find_median_sorted_arrays([], [1])
1.0

>>> find_median_sorted_arrays([-1000], [1000])
0.0

>>> find_median_sorted_arrays([-1.1, -2.2], [-3.3, -4.4])
-2.75
"""
if not nums1 and not nums2:
raise ValueError("Both input arrays are empty.")

# Merge the arrays into a single sorted array.
merged = sorted(nums1 + nums2)
total = len(merged)

if total % 2 == 1: # If the total number of elements is odd
return float(merged[total // 2]) # then return the middle element

# If the total number of elements is even, calculate
# the average of the two middle elements as the median.
middle1 = merged[total // 2 - 1]
middle2 = merged[total // 2]
return (float(middle1) + float(middle2)) / 2.0


if __name__ == "__main__":
import doctest

doctest.testmod()