Given two numbers `arr1` and `arr2` in base -2, return the result of adding them together.

Each number is given in array format: as an array of 0s and 1s, from most significant bit to least significant bit. For example, `arr = [1,1,0,1]` represents the number `(-2)^3 + (-2)^2 + (-2)^0 = -3`. A number `arr` in array, format is also guaranteed to have no leading zeros: either `arr == [0]` or `arr[0] == 1`.

Return the result of adding `arr1` and `arr2` in the same format: as an array of 0s and 1s with no leading zeros.

Example 1:

    Input: arr1 = [1,1,1,1,1], arr2 = [1,0,1]
    Output: [1,0,0,0,0]
    Explanation: arr1 represents 11, arr2 represents 5, the output represents 16.

Example 2:

    Input: arr1 = [0], arr2 = [0]
    Output: [0]

Example 3:

    Input: arr1 = [0], arr2 = [1]
    Output: [1]

Constraints:

- `1 <= arr1.length, arr2.length <= 1000`
- `arr1[i]` and `arr2[i]` are `0` or `1`
- `arr1` and `arr2` have no leading zeros