#include <bits/stdc++.h>
using namespace std;
int g(int x) {
  int t = 0, k = 1;
  while (x) {
    t += x % 10 * k;
    if (x % 10) k *= 10;
    x /= 10;
  }
  return t;
}
int main() {
  int n, m;
  cin >> n >> m;
  cout << (g(n) + g(m) == g(n + m) ? "YES" : "NO") << endl;
  return 0;
}
