n,k = map(int,input().split())
A = sorted(list(map(int,input().split())),reverse=True)

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