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

A.sort(reverse=True)

ans = 0
for i in range(2**(N-1)):
    k = K
    for j in range(N-1):
        if i & (1<<j):
            k %= A[j]
    ans = max(ans, k%A[-1])
print(ans)