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

print(ans)