from Crypto.Util.number import long_to_bytes


def inv(a, m):
    m0 = m
    x0 = 0
    x1 = 1

    if m == 1:
        return 0

    while a > 1:
        q = a // m
        t = m
        m = a % m
        a = t
        t = x0
        x0 = x1 - q * x0
        x1 = t

    if x1 < 0:
        x1 = x1 + m0

    return x1


def findMinX(num, rem, k):
    prod = 1
    for i in range(0, k):
        prod = prod * num[i]
    result = 0

    for i in range(0, k):
        pp = prod // num[i]
        result = result + rem[i] * inv(pp, num[i]) * pp

    return result % prod


rem = [7, 4, 9]
num = [17, 23, 37]
k = len(num)
a = findMinX(num, rem, k)
cipher_text = 25183524468752482838730336135334402772668615375346038
flag = cipher_text ^ a

print("a ==", a)
print(long_to_bytes(flag).decode('UTF-8'))