import java.util.Scanner;
 
public class Main{
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int numa = scan.nextInt();
        int numb = scan.nextInt();
        int numc = scan.nextInt();
        int numd = scan.nextInt(); 
        int i;
        for(i=0;i<10000;i++){
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          }        
        scan.close();
    }
} import java.util.Scanner; Scanner java.util public class Main{
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int numa = scan.nextInt();
        int numb = scan.nextInt();
        int numc = scan.nextInt();
        int numd = scan.nextInt(); 
        int i;
        for(i=0;i<10000;i++){
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          }        
        scan.close();
    }
} Main public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int numa = scan.nextInt();
        int numb = scan.nextInt();
        int numc = scan.nextInt();
        int numd = scan.nextInt(); 
        int i;
        for(i=0;i<10000;i++){
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          }        
        scan.close();
    } main {
        Scanner scan = new Scanner(System.in);
        int numa = scan.nextInt();
        int numb = scan.nextInt();
        int numc = scan.nextInt();
        int numd = scan.nextInt(); 
        int i;
        for(i=0;i<10000;i++){
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          }        
        scan.close();
    } Scanner scan = new Scanner(System.in); scan new Scanner(System.in) int numa = scan.nextInt(); numa scan.nextInt() scan.nextInt scan int numb = scan.nextInt(); numb scan.nextInt() scan.nextInt scan int numc = scan.nextInt(); numc scan.nextInt() scan.nextInt scan int numd = scan.nextInt(); numd scan.nextInt() scan.nextInt scan int i; i for(i=0;i<10000;i++){
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          } i=0; i=0 i 0 i<10000 i 10000 i++ i++ i {
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          } {
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          } if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                } i%2 == 0 i%2 i 2 0 {
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                } if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;} numc>0 numc 0 {
                    numc = numc - numb;} numc = numc - numb numc numc - numb numc numb {
                    System.out.println("Yes");
                    break;} System.out.println("Yes") System.out.println System.out System System.out "Yes" break; {
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                } if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;} numa>0 numa 0 {
                    numa = numa - numd;} numa = numa - numd numa numa - numd numa numd {
                    System.out.println("No");
                    break;} System.out.println("No") System.out.println System.out System System.out "No" break; scan.close() scan.close scan String[] args args public class Main{
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int numa = scan.nextInt();
        int numb = scan.nextInt();
        int numc = scan.nextInt();
        int numd = scan.nextInt(); 
        int i;
        for(i=0;i<10000;i++){
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          }        
        scan.close();
    }
} public class Main{
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int numa = scan.nextInt();
        int numb = scan.nextInt();
        int numc = scan.nextInt();
        int numd = scan.nextInt(); 
        int i;
        for(i=0;i<10000;i++){
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          }        
        scan.close();
    }
} Main
import java.util.Scanner;
 
public class Main{
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int numa = scan.nextInt();
        int numb = scan.nextInt();
        int numc = scan.nextInt();
        int numd = scan.nextInt(); 
        int i;
        for(i=0;i<10000;i++){
            if(i%2 == 0){
                if(numc>0){
                    numc = numc - numb;}
                else{
                    System.out.println("Yes");
                    break;}
                }
            else{
                if(numa>0){
                    numa = numa - numd;}
                else{
                    System.out.println("No");
                    break;}
                }        
          }        
        scan.close();
    }
}