import sys,heapq
input = sys.stdin.buffer.readline
n,k=map(int,input().split())
A=sorted([int(i) for i in input().split()],reverse=True)
ans=0
for i in range(2**(n-1)):
  cur=k
  for j in range(n-1):
    if i&(1<<j):
      cur%=A[j]
  ans=max(ans,cur%A[-1])
print(ans)