text: #include <bits/stdc++.h>
  
  using namespace std;
  
  string kangaroo(int x1, int v1, int x2, int v2) {
      double intersection = (static_cast<double>(x2) - x1) / (v1 - v2);
      if (intersection - floor(intersection) < 0.0001 && intersection > 0)
          return "YES";
      return "NO";
  }
  
  int main() {
      int x1;
      int v1;
      int x2;
      int v2;
      cin >> x1 >> v1 >> x2 >> v2;
      string result = kangaroo(x1, v1, x2, v2);
      cout << result << endl;
      return 0;
  }
  