X, A, Y, B = map(int, input().split())

mx = 10 ** 6
isprime = [True] * (mx + 1)
prime_list = []
isprime[0], isprime[1] = False, False
for i in range(2, mx):
    if isprime[i] == False:
        continue
    prime_list.append(i)
    j = 2 * i
    while j <= mx:
        isprime[j] = False
        j += i

for p in prime_list:
    cnta, cntb = 0, 0
    while X % p == 0:
        X //= p
        cnta += 1
    while Y % p == 0:
        Y //= p
        cntb += 1
    if cnta * X < cntb * Y:
        print('No')
        exit()

if X != Y:
    print('No')
elif X == 1:
    print('Yes')
else:
    if A < B:
        print('No')
    else:
        print('Yes')