def read_data():
    N = int(input())
    A = list(set(map(int, input().split())))
    return A

def solve(A):
    digits = len(bin(max(A))) - 2
    index = 1 << digits
    N = len(A)
    rank_upper_bound = min(digits, N)
    for rank in range(1, rank_upper_bound + 1):
        Ar = max(A)
        if Ar == 0:
            rank -= 1
            break
        index = 1 << (len(bin(Ar)) - 3)
        for i in range(N):
            if A[i] & index:
                A[i] ^= Ar
    return 1 << rank

A = read_data()
print(solve(A))