N, K = map(int, input().split())
A = list(map(int, input().split()))
A.sort(reverse=True)
from itertools import groupby, accumulate, product, permutations, combinations

ans = 0
for p in product([0,1],repeat=N-1):
    k = K
    for i in range(N-1):
        if p[i]==1:
            k %= A[i]
    k%=A[-1]
    ans = max(ans,k)
print(ans)