leetCode 之 两个二进制数相加
题目: * Given two binary strings, return their sum (also a binary string). * * For example, a = "11" b = "1" Return "100". * * 题目翻译: * * 给定两个二进制字符串,返回它们的和(也是一个二进制字符串)。 例如, a = "11" b =