from math import gcd, lcm


# n の桁数
def digit(n: int) -> int:
    return len(str(n))


def solve():
    N = int(input())
    A = [int(s) for s in input().split()]

    ans = 1
    for i in range(1, N):
        m = 10 ** digit(A[i])
        ans = lcm(ans, m // gcd(A[i], m))

    print(ans)


if __name__ == "__main__":
    T = int(input())

    for _ in range(T):
        solve()