text: #include <bits/stdc++.h>
  using namespace std;
  bool isTwoDifferentSign(signed int a, signed int b)
  {
      return ((a ^ b) < 0);
  }
  int main()
  {
      signed int x, y;
      cin >> x >> y;
      if (isTwoDifferentSign(x, y))
          cout << "Yes" << endl;
      else
          cout << "No" << endl;
      return 0;
  }