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

 

x = -(-a // d)

y = -(-c // b)

 

if x >= y:

  print("Yes")

else:

  print("No")
a,b,c,d = list(map(int, input().split()))



while True:

    c -= b

    a -= d

    if c <= 0:

        print("Yes")

        break

    elif a <= 0:

        print("No")

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

a, b, c, d = list(map(int, input().split()))
while True:
    c -= b
    a -= d
    if c <= 0:
        print("Yes")
        break
    elif a <= 0:
        print("No")
        break

-x = -(-a // d) -y = -(-c // b) -if x >= y: -    print("Yes") -else: -    print("No") +while True: +    c -= b +    a -= d +    if c <= 0: +        print("Yes") +        break +    elif a <= 0: +        print("No") +        break