#include <bits/stdc++.h>
using namespace std;
bool great(pair<int, int> a, pair<int, int> b) { return (a.first < b.first); }
int search(vector<int> v, int size, int a) {
  int l = 0, r = size - 1;
  int result = size;
  while (l <= r) {
    int mid = (l + r) / 2;
    if (v[mid] > a) {
      result = mid;
      r = mid - 1;
    } else {
      l = mid + 1;
    }
  }
  return result;
}
template <class c>
c gcd(c a, c b) {
  if (b == 0) return a;
  gcd(b, a % b);
}
bool check(long long int a, long long int b, long long int c, long long int d) {
  return ((a + b == c + d) || (a - b == c - d) ||
          (abs(a - c) + abs(b - d) <= 3));
}
int solve(long long int a, long long int b, long long int c, long long int d) {
  if (a > c) {
    swap(a, c);
    swap(b, d);
  }
  if (a == c && b == d)
    return 0;
  else if (check(a, b, c, d))
    return 1;
  else if ((a + b) % 2 == (c + d) % 2)
    return 2;
  for (int i = -2; i <= 2; i++) {
    for (int j = -2; j <= 2; j++) {
      long long int p = c + i;
      long long int q = d + j;
      if (check(a, b, p, q)) return 2;
    }
  }
  if ((check(a, b, c + 3, d) || check(a, b, c - 3, d) ||
       check(a, b, c, d + 3) || check(a, b, c + 3, d)))
    return 2;
  return 3;
}
bool prime(int n) {
  for (int i = 2; i <= sqrt(n); i++) {
    if (n % i == 0) return 0;
  }
  return 1;
}
int check(int n, int m, int r, int c) { return abs(n - r) + abs(m - c); }
long long f(long long x) {
  long long z = sqrtl(x);
  long long ans = 1e18;
  for (int i = -5; i <= 5; i++) {
    long long z2 = z - i;
    if (z2 > x || z2 < 1) continue;
    ans = min(ans, z2 - 2 + (x + z2 - 1) / z2);
  }
  return ans;
}
int toggle(int a) {
  if (a == 1) return 0;
  return 1;
}
void run() {
  string a, b;
  cin >> a >> b;
  for (int i = 0; i < a.length(); i++) {
    if (a[i] != b[i])
      cout << '1';
    else
      cout << '0';
  }
}
int main() { run(); }
