N,K = map(int, input().split(' '))
A = input().split(' ')
print(A)
A_int = [int(A[i]) for i in range(N)]
A_list = sorted(A_int, reverse = True)
amari_max = 0
M=K
for i in range(N):
	K=M
	for j in range(i,N):
		K = K%A_list[j]
	if amari_max<K:
		amari_max = K
print(amari_max)