Adding Two Negabinary Numbers

class Solution {
public:
    vector<int> addNegabinary(vector<int>& a, vector<int>& b) {
        vector<int> out;
        int i = a.size() - 1, j = b.size() - 1, carry = 0;
        while (i >= 0 || j >= 0 || carry) {
            int x = (i >= 0) ? a[i--] : 0;
            int y = (j >= 0) ? b[j--] : 0;
            int s = x + y + carry;
            if (s >= 2) { s -= 2; carry = -1; }
            else if (s < 0) { s += 2; carry = 1; }
            else carry = 0;
            out.push_back(s);
        }
        while (out.size() > 1 && out.back() == 0) out.pop_back();
        reverse(out.begin(), out.end());
        return out;
    }
};

func addNegabinary(a []int, b []int) []int {
    out := []int{}
    i, j, carry := len(a)-1, len(b)-1, 0
    for i >= 0 || j >= 0 || carry != 0 {
        x, y := 0, 0
        if i >= 0 {
            x = a[i]
            i--
        }
        if j >= 0 {
            y = b[j]
            j--
        }
        s := x + y + carry
        if s >= 2 {
            s -= 2
            carry = -1
        } else if s < 0 {
            s += 2
            carry = 1
        } else {
            carry = 0
        }
        out = append(out, s)
    }
    for len(out) > 1 && out[len(out)-1] == 0 {
        out = out[:len(out)-1]
    }
    for l, r := 0, len(out)-1; l < r; l, r = l+1, r-1 {
        out[l], out[r] = out[r], out[l]
    }
    return out
}

from typing import List

class Solution:
    def addNegabinary(self, arr1: List[int], arr2: List[int]) -> List[int]:
        out: List[int] = []
        i, j, carry = len(arr1) - 1, len(arr2) - 1, 0
        while i >= 0 or j >= 0 or carry:
            x = arr1[i] if i >= 0 else 0
            y = arr2[j] if j >= 0 else 0
            s = x + y + carry
            if s >= 2:
                s -= 2
                carry = -1
            elif s < 0:
                s += 2
                carry = 1
            else:
                carry = 0
            out.append(s)
            i -= 1
            j -= 1
        while len(out) > 1 and out[-1] == 0:
            out.pop()
        out.reverse()
        return out

var addNegabinary = function(arr1, arr2) {
    const out = [];
    let i = arr1.length - 1, j = arr2.length - 1, carry = 0;
    while (i >= 0 || j >= 0 || carry !== 0) {
        const x = i >= 0 ? arr1[i--] : 0;
        const y = j >= 0 ? arr2[j--] : 0;
        let s = x + y + carry;
        if (s >= 2) { s -= 2; carry = -1; }
        else if (s < 0) { s += 2; carry = 1; }
        else carry = 0;
        out.push(s);
    }
    while (out.length > 1 && out[out.length - 1] === 0) out.pop();
    return out.reverse();
};

class Solution {
    public int[] addNegabinary(int[] arr1, int[] arr2) {
        List<Integer> out = new ArrayList<>();
        int i = arr1.length - 1, j = arr2.length - 1, carry = 0;
        while (i >= 0 || j >= 0 || carry != 0) {
            int x = i >= 0 ? arr1[i--] : 0;
            int y = j >= 0 ? arr2[j--] : 0;
            int s = x + y + carry;
            if (s >= 2) { s -= 2; carry = -1; }
            else if (s < 0) { s += 2; carry = 1; }
            else carry = 0;
            out.add(s);
        }
        while (out.size() > 1 && out.get(out.size() - 1) == 0) {
            out.remove(out.size() - 1);
        }
        int n = out.size();
        int[] ans = new int[n];
        for (int k = 0; k < n; k++) ans[k] = out.get(n - 1 - k);
        return ans;
    }
}

function addNegabinary(arr1: number[], arr2: number[]): number[] {
    const out: number[] = [];
    let i = arr1.length - 1, j = arr2.length - 1, carry = 0;
    while (i >= 0 || j >= 0 || carry !== 0) {
        const x = i >= 0 ? arr1[i--] : 0;
        const y = j >= 0 ? arr2[j--] : 0;
        let s = x + y + carry;
        if (s >= 2) { s -= 2; carry = -1; }
        else if (s < 0) { s += 2; carry = 1; }
        else carry = 0;
        out.push(s);
    }
    while (out.length > 1 && out[out.length - 1] === 0) out.pop();
    return out.reverse();
}