67. Add Binary

/**
 * Problem: LeetCode 67 - Add Binary
 * Difficulty: Easy
 * Language: Java
 * Author: CodeByTushu
 */
class Solution {
    public String addBinary(String a, String b) {
        StringBuilder sb = new StringBuilder();
        int i = a.length() - 1;
        int j = b.length() - 1;
        int carry = 0;

        while (i >= 0 || j >= 0 || carry > 0) {
            int sum = carry;
            if (i >= 0) {
                sum += a.charAt(i--) - '0';
            }
            if (j >= 0) {
                sum += b.charAt(j--) - '0';
            }
            sb.append(sum % 2);
            carry = sum / 2;
        }

        return sb.reverse().toString();
    }
}

"""
Problem: LeetCode 67 - Add Binary
Difficulty: Easy
Language: Python
Author: CodeByTushu
"""
class Solution:
    def addBinary(self, a: str, b: str) -> str:
        res = []
        i, j = len(a) - 1, len(b) - 1
        carry = 0

        while i >= 0 or j >= 0 or carry:
            total = carry
            if i >= 0:
                total += int(a[i])
                i -= 1
            if j >= 0:
                total += int(b[j])
                j -= 1
            res.append(str(total % 2))
            carry = total // 2

        return "".join(reversed(res))

/**
 * Problem: LeetCode 67 - Add Binary
 * Difficulty: Easy
 * Language: C++
 * Author: CodeByTushu
 */
#include <string>
#include <algorithm>

using namespace std;

class Solution {
public:
    string addBinary(string a, string b) {
        string res = "";
        int i = a.length() - 1;
        int j = b.length() - 1;
        int carry = 0;

        while (i >= 0 || j >= 0 || carry > 0) {
            int sum = carry;
            if (i >= 0) {
                sum += a[i--] - '0';
            }
            if (j >= 0) {
                sum += b[j--] - '0';
            }
            res += to_string(sum % 2);
            carry = sum / 2;
        }

        reverse(res.begin(), res.end());
        return res;
    }
};

/**
 * Problem: LeetCode 67 - Add Binary
 * Difficulty: Easy
 * Language: JavaScript
 * Author: CodeByTushu
 */
/**
 * @param {string} a
 * @param {string} b
 * @return {string}
 */
var addBinary = function(a, b) {
    let i = a.length - 1;
    let j = b.length - 1;
    let carry = 0;
    const res = [];

    while (i >= 0 || j >= 0 || carry > 0) {
        let sum = carry;
        if (i >= 0) {
            sum += a.charCodeAt(i--) - 48;
        }
        if (j >= 0) {
            sum += b.charCodeAt(j--) - 48;
        }
        res.push(sum % 2);
        carry = Math.floor(sum / 2);
    }

    return res.reverse().join('');
};