n = int(input())
a = list(map(int,input().split()))
cnt = 0
#n <= 1<<60 以下くらい
def popcnt(n):
  c = (n & 0x5555555555555555) + ((n>>1) & 0x5555555555555555)
  c = (c & 0x3333333333333333) + ((c>>2) & 0x3333333333333333)
  c = (c & 0x0f0f0f0f0f0f0f0f) + ((c>>4) & 0x0f0f0f0f0f0f0f0f)
  c = (c & 0x00ff00ff00ff00ff) + ((c>>8) & 0x00ff00ff00ff00ff)
  c = (c & 0x0000ffff0000ffff) + ((c>>16) & 0x0000ffff0000ffff)
  c = (c & 0x00000000ffffffff) + ((c>>32) & 0x00000000ffffffff)
  return c
for i in range(n):
  cnt += popcnt(a[i])
ans = 0
for i in range(min(cnt, 16)):
  ans += pow(2, 15-i)

print(ans)