def subsetXORSum(nums: list[int]) -> int:
    size = len(nums)
    xor = 0

    for i in range(1, 2 ** size):
        subset_map = format(i, f"0{size}b")
        subset_xor = 0
        for index in range(size):
            if subset_map[index] == '1':
                subset_xor ^= nums[index]
        xor += subset_xor

    return xor