Given two binary strings, return their sum (also a binary string).
The input strings are both non-empty and contains only characters 1 or 0.
Example 1: Input: a = "11", b = "1" Output: "100" Example 2: Input: a = "1010", b = "1011" Output: "10101"
难度: easy
题目:
给定两个二进制字符串,返回它们的和(也是二进制字符串)。
字符串都不为空且只有0、1组成。
Runtime: 2 ms, faster than 95.70% of Java online submissions for Add Binary.
Memory Usage: 26.2 MB, less than 54.54% of Java online submissions for Add Binary.
public class Solution { public String addBinary(String a, String b) { int i = a.length() - 1, j = b.length() - 1, carry = 0; StringBuilder result = new StringBuilder(); while (i >= 0 || j >= 0) { char ac = i >= 0 ? a.charAt(i) : '0'; char bc = j >= 0 ? b.charAt(j) : '0'; int sum = (ac - '0') + (bc - '0') + carry; result.append(sum % 2); carry = sum / 2; i--; j--; } if (carry > 0) { result.append(1); } return new String(result.reverse()); } }