module Main (main) where
import Data.Bits

import qualified Data.ByteString as B
import qualified Data.ByteString.Char8 as B
import Control.Applicative
import Data.Maybe(fromJust)
import Data.List
import Debug.Trace
default (Int)

getInt :: IO Int
getInt = fst . fromJust . B.readInt <$> B.getLine
getInts :: IO [Int]
getInts = map (fst . fromJust . B.readInt) <$> B.words <$> B.getLine

main :: IO ()
main = do
  _n <- getInt
  as <- getInts
  print $ solve as

solve :: [Int] -> Int
solve = (2^) . length . traceShowId . sweep 60



sweep :: Int -> [Int] -> [Int]
sweep (-1) xs = xs
sweep b xs = case find (`testBit` b) xs of
  Nothing -> sweep (b-1) xs
  Just x  -> let
    xs' = map (f x) xs
    xs'' = filter (/= 0) xs'
    in
      x: sweep (b-1) xs''
  where
    f :: Int -> Int -> Int
    f x y = if 0 == (y .&. (1 `shiftL` b))
            then y
            else y `xor` x