import sys

input = sys.stdin.readline



# B - Battle

def takahashi_win():

	A, B, C, D = list(map(int, input().split()))

	i = 0



	while True:

		if i % 2 == 0:

			if C-B <= 0:

				return True

			else:

				C -= B

		else:

			if A-D <= 0:

				return False

			else:

				A -= D

		

		i += 1





if takahashi_win():

	print('Yes')

else:

	print('No')
import sys

input = sys.stdin.readline



# B - Battle

def win_takahashi(A, B, C, D):



	for i in range(200):

		if i % 2 == 0:

			if B >= C:

				return True

			else:

				C -= B

		else:

			if D >= A:

				return False

			else:

				A -= D

			



A, B, C, D = list(map(int, input().split()))



if win_takahashi(A, B, C, D):

	print('Yes')

else:

	print('No')

import sys

input = sys.stdin.readline
# B - Battle
def takahashi_win():
    A, B, C, D = list(map(int, input().split()))
    i = 0
    while True:
        if i % 2 == 0:
            if C - B <= 0:
                return True
            else:
                C -= B
        else:
            if A - D <= 0:
                return False
            else:
                A -= D
        i += 1


if takahashi_win():
    print("Yes")
else:
    print("No")

import sys

input = sys.stdin.readline
# B - Battle
def win_takahashi(A, B, C, D):
    for i in range(200):
        if i % 2 == 0:
            if B >= C:
                return True
            else:
                C -= B
        else:
            if D >= A:
                return False
            else:
                A -= D


A, B, C, D = list(map(int, input().split()))
if win_takahashi(A, B, C, D):
    print("Yes")
else:
    print("No")

-def takahashi_win(): -    A, B, C, D = list(map(int, input().split())) -    i = 0 -    while True: +def win_takahashi(A, B, C, D): +    for i in range(200): -            if C - B <= 0: +            if B >= C: -            if A - D <= 0: +            if D >= A: -        i += 1 -if takahashi_win(): +A, B, C, D = list(map(int, input().split())) +if win_takahashi(A, B, C, D):