import java.util.Scanner;

public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int b = sc.nextInt();
    int c = sc.nextInt();
    int d = sc.nextInt();
    int aCount = a % d == 0 ? a / d : a / d + 1;
    int bCount = c % b == 0 ? c / b : c / b + 1;
    System.out.println(aCount >= bCount ? "Yes" : "No");
  }

} import java.util.Scanner; Scanner java.util public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int b = sc.nextInt();
    int c = sc.nextInt();
    int d = sc.nextInt();
    int aCount = a % d == 0 ? a / d : a / d + 1;
    int bCount = c % b == 0 ? c / b : c / b + 1;
    System.out.println(aCount >= bCount ? "Yes" : "No");
  }

} Main public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int b = sc.nextInt();
    int c = sc.nextInt();
    int d = sc.nextInt();
    int aCount = a % d == 0 ? a / d : a / d + 1;
    int bCount = c % b == 0 ? c / b : c / b + 1;
    System.out.println(aCount >= bCount ? "Yes" : "No");
  } main {
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int b = sc.nextInt();
    int c = sc.nextInt();
    int d = sc.nextInt();
    int aCount = a % d == 0 ? a / d : a / d + 1;
    int bCount = c % b == 0 ? c / b : c / b + 1;
    System.out.println(aCount >= bCount ? "Yes" : "No");
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int a = sc.nextInt(); a sc.nextInt() sc.nextInt sc int b = sc.nextInt(); b sc.nextInt() sc.nextInt sc int c = sc.nextInt(); c sc.nextInt() sc.nextInt sc int d = sc.nextInt(); d sc.nextInt() sc.nextInt sc int aCount = a % d == 0 ? a / d : a / d + 1; aCount a % d == 0 ? a / d : a / d + 1 a % d == 0 a % d a d 0 a / d a d a / d + 1 a / d a d 1 int bCount = c % b == 0 ? c / b : c / b + 1; bCount c % b == 0 ? c / b : c / b + 1 c % b == 0 c % b c b 0 c / b c b c / b + 1 c / b c b 1 System.out.println(aCount >= bCount ? "Yes" : "No") System.out.println System.out System System.out aCount >= bCount ? "Yes" : "No" aCount >= bCount aCount bCount "Yes" "No" String[] args args public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int b = sc.nextInt();
    int c = sc.nextInt();
    int d = sc.nextInt();
    int aCount = a % d == 0 ? a / d : a / d + 1;
    int bCount = c % b == 0 ? c / b : c / b + 1;
    System.out.println(aCount >= bCount ? "Yes" : "No");
  }

} public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int b = sc.nextInt();
    int c = sc.nextInt();
    int d = sc.nextInt();
    int aCount = a % d == 0 ? a / d : a / d + 1;
    int bCount = c % b == 0 ? c / b : c / b + 1;
    System.out.println(aCount >= bCount ? "Yes" : "No");
  }

} Main
import java.util.Scanner;

public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int a = sc.nextInt();
    int b = sc.nextInt();
    int c = sc.nextInt();
    int d = sc.nextInt();
    int aCount = a % d == 0 ? a / d : a / d + 1;
    int bCount = c % b == 0 ? c / b : c / b + 1;
    System.out.println(aCount >= bCount ? "Yes" : "No");
  }

}