text: #include <iostream>
  using namespace std;
  
  int main()
  {
      int X, Y;
      cin >> X >> Y;
      if(X < Y && (X+3) > Y) {
          cout << "Yes" << endl;
      } else if(X > Y && X < (Y+3)) {
          cout << "Yes" << endl;
      } else {
          cout << "No" << endl;
      }
      return 0;
  }
  