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