leetcode Add Binary

class Solution {
public:
    string addBinary(string a, string b) {
        int aL = a.length();
    int bL = b.length();
    int cL;
    if (aL > bL)
        cL = aL + 1;
    else
        cL = bL + 1;
    char *c = new char[cL+1];
    int k = aL-1;
    int j = bL - 1;
    int flag = 0;
    for (int i = cL - 1; i >= 1; i--)
    {
        if (k == -1)
        {
            int sum = b[j] - '0' + flag;
            c[i] = sum%2+'0';
            flag = sum / 2;
            j--;
        }
        else if (j == -1)
        {
            int sum = a[k] - '0' + flag;
            c[i] = sum % 2+'0';
            flag = sum / 2;
            k--;
        }
        else
        {
            int sum = flag + a[k]-'0' + b[j]-'0';
            c[i] = sum % 2 + '0';
            flag = sum / 2;
            k--;
            j--;
        }
    }
    c[0] = flag + '0';
    c[cL] = 0;
    if (c[0] == '0')
        return &c[1];
    else
        return c;
    }
};

 没什么好讲的，好像也只有把代码写的好看一些，这个以后多加锻炼！