# This Python file uses the following encoding: utf-8



# if __name__ == "__main__":

#     pass

a, b, c, d = list(map(int, input().split()))

'''

while a > 0 and c > 0:

    c -= b

    a -= d

if c <= 0:

    print("Yes")

else:

    print("No")

'''

if  -(-c//b) <= -(-a//d):

    print("Yes")

else:

    print("No")

a, b, c, d = list(map(int, input().split()))



if  -(-c//b) <= -(-a//d):

    print("Yes")

else:

    print("No")

# This Python file uses the following encoding: utf-8
# if __name__ == "__main__":
#     pass
a, b, c, d = list(map(int, input().split()))
"""
while a > 0 and c > 0:
    c -= b
    a -= d
if c <= 0:
    print("Yes")
else:
    print("No")
"""
if -(-c // b) <= -(-a // d):
    print("Yes")
else:
    print("No")

a, b, c, d = list(map(int, input().split()))
if -(-c // b) <= -(-a // d):
    print("Yes")
else:
    print("No")

-# This Python file uses the following encoding: utf-8 -# if __name__ == "__main__": -#     pass -""" -while a > 0 and c > 0: -    c -= b -    a -= d -if c <= 0: -    print("Yes") -else: -    print("No") -"""