//
//  main.cpp
//  xor_equ
//
//  Created by Qing Liu on 15/11/3.
//  Copyright © 2015年 Qing Liu. All rights reserved.
//

#include <iostream>
#include <cstdio>
#include <cstring>
#define maxn 11000
using namespace std;
typedef long long ll;
ll a[maxn];
int n;
bool vis[maxn];
ll maxx=0;
void DFS(int s,ll t){
    if (t>maxx) {
        maxx=t;
    }
    for(int i=s+1;i<=n;i++){
        DFS(i,t xor a[i]);
    }
}
int main() {
    freopen("xor_equ.in", "r", stdin);
    freopen("xor_equ.out", "w", stdout);
    cin>>n;
    for (int i=1; i<=n; i++) {
        cin>>a[i];
    }
    DFS(0,0);
    cout<<maxx;
    return 0;
}