Add Binary

easy

bitsTime: O(max(m, n)) where m and n are lengths of a and bSpace: O(1) modifying input string in placeFrequency: 3

Given two binary strings a and b, return their sum as a binary string.

Constraints: 1 <= a.length, b.length <= 10^4. a and b consist only of '0' or '1' characters. Each string does not contain leading zeros except for the zero itself.

Example 1:

Input: a = "11", b = "1"
Output: "100"

Example 2:

Input: a = "1010", b = "1011"
Output: "10101"

bit-manipulationmath

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