code is success but one test is not getting passed
why?..plzzz make it correct all test cases
#include<bits/stdc++.h>
using namespace std;
int main()
{
int T;
cin>>T;
while(T–)
{
string s1;
string s2;
cin>>s1;
cin>>s2;
string result;
for(int i=0;i<s1.length();i++)
{
if(s1[i]==s2[i])
result[i]=‘0’;
else
result[i]=‘1’;
}
for(int i=0;i<s1.length();i++)
{
cout<<result[i];
}
}cout<<endl;
return 0;
}