#include <iostream> #include<cmath> using namespace std; int main() { string a,b,c; cin>>a>>b; int len=a.size(); for(int i=0;i<len;i++) { if(a[i]=='1' && b[i]=='1') c[i]='1'; if(a[i]=='1' && b[i]=='0') c[i]='0'; if(b[i]=='1' && a[i]=='0') c[i]='0'; if(a[i]=='0' && b[i]=='0') c[i]='1'; } for(int j=0;j<len;j++) { cout<<c[j]; } return 0; }