p, q, x, y = map(int, input().split())
while y % 10 == 0 or int(str(y)[::-1]) % p == 0:
    y += q
ans = int(str(y)[::-1])
t = 0
while ans * pow(10, t, p) % p != x:
    t += 1
print(str(ans) + '0' * t)