#include <iostream>
#include <string>
using namespace std;

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);

    string A, B; cin >> A >> B;
    if (A.size() < B.size()) swap(A, B);
    string S(A.size()-B.size(), '0');
    B = S + B;
    for (int i = 0; i < A.size(); i++)
        cout << (A[i] == B[i] ? 0 : 1);
    cout << "\n";
}