LeetCode:Add Binary

Add Binary

Total Accepted: 64222 Total
Submissions: 252110 Difficulty: Easy

Given two binary strings, return their sum (also a binary string).
For example,

a =

"11"

b =

"1"

Return

"100"

.

code:

class Solution {
public:
    string addBinary(string a, string b) {
        int carry=0;
        int i=a.size()-1,j=b.size()-1;
        string ret="";
        while(i!=-1 || j!=-1 || carry) {
            carry += i>=0 ? a[i--]-'0':0;
            carry += j>=0 ? b[j--]-'0':0;
            ret = char(carry % 2 + '0') + ret;
            carry /= 2;
        }
        return ret;
    }
};