N,K = map(int,input().split())
A = list(map(int,input().split()))
A.sort(reverse=True)
ans = 0
for i in range(2**N):
    v=K
    for j in range(N):
        if 2**j&i>0:
            v%=A[j]
    ans = max(ans,v%A[-1])
print(ans)