Given two binary strings, return their sum (also a binary string).
For example,
a = "11"
b = "1"
Return "100".
class Solution {
public:
string addBinary(string a, string b) {
int fw = 0;
string result = "";
for(int i = a.size()-1,j=b.size()-1;i>=0||j>=0;i--,j--){
int ag = i>=0?a[i]-'0':0;
int bg = j>=0?b[j]-'0':0;
int tmp = (ag+bg+fw)%2;
fw = (ag+bg+fw)/2;
result = char(tmp+'0')+result;
}
if(fw==1){
result = '1'+result;
}
return result;
}
};
