#include<cstring>
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<cmath>
#include<vector>
#include<queue>
using namespace std;
int n,m;
long long maxx=0,ans,a[10005],p,q;
bool v[10005];
void dfs(int t)
{
	if(t==n+1) return;
	for(int i=1;i<=n;i++)
	   if(!v[i])
	   {
	   	  v[i]=1;
		  p=ans;
		  ans=ans xor a[i];
		  if(ans>maxx)
		     maxx=ans;
		  t++;
		  dfs(t);
		  t--;
		  v[i]=0;
		  ans=p;
	   }
}
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(1);
	cout<<maxx;
}