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)):
    res = k
    for i in range(n - 1):
        if (bit >> i) & 1:
            res %= A[i]
    res %= A[n - 1]
    ans = max(ans, res)
print(ans)