from collections import Counter


def prime_factorize(n):
    a = []
    while n % 2 == 0:
        a.append(2)
        n //= 2
    f = 3
    while f * f <= n:
        if n % f == 0:
            a.append(f)
            n //= f
        else:
            f += 2
    if n != 1:
        a.append(n)
    return Counter(a)

x, a, y, b = map(int, input().split())
cx = prime_factorize(x)
cy = prime_factorize(y)
for p in set(cx.keys()) | set(cy.keys()):
    if a * cx[p] < b * cy[p]: exit(print("No"))
print("Yes")