from itertools import product
N, K = map(int,input().split())
A = list(map(int, input().split()))

A.sort(reverse=True)
B = A[:-1]
ans = 0
for i in product([0,1], repeat=N-1):
    temp = K
    for idx,j in enumerate(i):
        if j:
            temp %= B[idx]
            
    ans = max(ans,temp%A[-1])
print(ans)