N, K = map(int, input().split())
A = list(map(int, input().split()))
A.sort(reverse=True)

ans = 0
for bit in range(1 << (N - 1)):
    tmp = K
    for i in range(N - 1):
        if bit >> i & 1:
            tmp %= A[i]
    tmp %= A[N - 1]
    ans = max(ans, tmp)

print(ans)