n, k = map(int, input().split())
a = list(map(int, input().split()))
a.sort(reverse=True)
ans = 0
for b in range(1, 1<<n):
    res = k
    for i in range(n-1):
        if (b>>i) & 1:
            res %= a[i]
    ans = max(ans, res%a[n-1])
print(ans)