Leetcode67二进制求和

1104

代码：

class Solution {public String addBinary(String a, String b) {StringBuffer ans = new StringBuffer();int n = Math.max(a.length(),b.length()),carry = 0;for(int i=0;i<n;i++){carry += i < a.length()?(a.charAt(a.length()-1-i)-'0'):0;carry += i < b.length()?(b.charAt(b.length()-1-i)-'0'):0;ans.append((char)(carry%2+'0'));carry /=2;}if(carry>0){ans.append('1');}return ans.reverse().toString();}
}