题解 | #二进制求和#

class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param A string字符串 
     * @param B string字符串 
     * @return string字符串
     */
    string binaryAdd(string A, string B) {
        // write code here
        int len1 = A.size(), len2 = B.size();
        int cap = 0;
        int i = len1 - 1, j = len2 - 1;
        string ans = "";
        while (i >= 0 || j >= 0) {
            int a = (len1 - i <= len1) ? A[i]-'0':0;
            int b = (len2 - j <= len2) ? B[j]-'0':0;
            i--, j--;
            int t = a + b + cap;
            ans = to_string(t%2) + ans;
            cap = t / 2;
        }
        if (cap) {
            ans = "1" + ans;
        }
        return ans;
    }
};