N, K = map(int, input().split())
A = list(map(int, input().split()))
A.sort(reverse=True)
ans = 0
for i in range(1 << (N - 1)):
    x = K
    for j in range(N - 1):
        if i >> j & 1:
            x %= A[j]
    ans = max(x % A[-1], ans)
print(ans)