## https://yukicoder.me/problems/no/1819


def main():
    P, Q, x, y = map(int, input().split())

    if y % 10 == 0:
        y += Q

    N = int(str(y)[::-1])
    n_array = [str(N)]
    n = N % P
    while n != x:
        n *= 10
        n %= P
        n_array.append("0")
    
    print("".join(n_array))


if __name__ == "__main__":
    main()