import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String line = scanner.nextLine();
        String[] arr = line.split(" ");
        int t_h = Integer.parseInt(arr[0]);
        int t_s = Integer.parseInt(arr[1]);
        int a_h = Integer.parseInt(arr[2]);
        int a_s = Integer.parseInt(arr[3]);

        boolean t_turn = true;

        while (t_h > 0 && a_h > 0) {
            if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            }
            t_turn = !t_turn;
        }

        if (t_h > 0) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String line = scanner.nextLine();
        String[] arr = line.split(" ");
        int t_h = Integer.parseInt(arr[0]);
        int t_s = Integer.parseInt(arr[1]);
        int a_h = Integer.parseInt(arr[2]);
        int a_s = Integer.parseInt(arr[3]);

        boolean t_turn = true;

        while (t_h > 0 && a_h > 0) {
            if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            }
            t_turn = !t_turn;
        }

        if (t_h > 0) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String line = scanner.nextLine();
        String[] arr = line.split(" ");
        int t_h = Integer.parseInt(arr[0]);
        int t_s = Integer.parseInt(arr[1]);
        int a_h = Integer.parseInt(arr[2]);
        int a_s = Integer.parseInt(arr[3]);

        boolean t_turn = true;

        while (t_h > 0 && a_h > 0) {
            if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            }
            t_turn = !t_turn;
        }

        if (t_h > 0) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    } main {
        Scanner scanner = new Scanner(System.in);
        String line = scanner.nextLine();
        String[] arr = line.split(" ");
        int t_h = Integer.parseInt(arr[0]);
        int t_s = Integer.parseInt(arr[1]);
        int a_h = Integer.parseInt(arr[2]);
        int a_s = Integer.parseInt(arr[3]);

        boolean t_turn = true;

        while (t_h > 0 && a_h > 0) {
            if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            }
            t_turn = !t_turn;
        }

        if (t_h > 0) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) String line = scanner.nextLine(); line scanner.nextLine() scanner.nextLine scanner String[] arr = line.split(" "); arr line.split(" ") line.split line " " int t_h = Integer.parseInt(arr[0]); t_h Integer.parseInt(arr[0]) Integer.parseInt Integer arr[0] arr 0 int t_s = Integer.parseInt(arr[1]); t_s Integer.parseInt(arr[1]) Integer.parseInt Integer arr[1] arr 1 int a_h = Integer.parseInt(arr[2]); a_h Integer.parseInt(arr[2]) Integer.parseInt Integer arr[2] arr 2 int a_s = Integer.parseInt(arr[3]); a_s Integer.parseInt(arr[3]) Integer.parseInt Integer arr[3] arr 3 boolean t_turn = true; t_turn true while (t_h > 0 && a_h > 0) {
            if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            }
            t_turn = !t_turn;
        } t_h > 0 && a_h > 0 t_h > 0 t_h 0 a_h > 0 a_h 0 {
            if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            }
            t_turn = !t_turn;
        } if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            } t_turn {
                a_h -= t_s;
            } a_h -= t_s a_h t_s {
                t_h -= a_s;
            } t_h -= a_s t_h a_s t_turn = !t_turn t_turn !t_turn t_turn if (t_h > 0) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        } t_h > 0 t_h 0 {
            System.out.println("Yes");
        } System.out.println("Yes") System.out.println System.out System System.out "Yes" {
            System.out.println("No");
        } System.out.println("No") System.out.println System.out System System.out "No" String[] args args public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String line = scanner.nextLine();
        String[] arr = line.split(" ");
        int t_h = Integer.parseInt(arr[0]);
        int t_s = Integer.parseInt(arr[1]);
        int a_h = Integer.parseInt(arr[2]);
        int a_s = Integer.parseInt(arr[3]);

        boolean t_turn = true;

        while (t_h > 0 && a_h > 0) {
            if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            }
            t_turn = !t_turn;
        }

        if (t_h > 0) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
} public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String line = scanner.nextLine();
        String[] arr = line.split(" ");
        int t_h = Integer.parseInt(arr[0]);
        int t_s = Integer.parseInt(arr[1]);
        int a_h = Integer.parseInt(arr[2]);
        int a_s = Integer.parseInt(arr[3]);

        boolean t_turn = true;

        while (t_h > 0 && a_h > 0) {
            if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            }
            t_turn = !t_turn;
        }

        if (t_h > 0) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String line = scanner.nextLine();
        String[] arr = line.split(" ");
        int t_h = Integer.parseInt(arr[0]);
        int t_s = Integer.parseInt(arr[1]);
        int a_h = Integer.parseInt(arr[2]);
        int a_s = Integer.parseInt(arr[3]);

        boolean t_turn = true;

        while (t_h > 0 && a_h > 0) {
            if (t_turn) {
                a_h -= t_s;
            } else {
                t_h -= a_s;
            }
            t_turn = !t_turn;
        }

        if (t_h > 0) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
}