#include<bits/stdc++.h>
#define ull unsigned long long
#define ll long long
using namespace std;
int nc;
ll n[10001];
ll ans;
void dg(ll p,int x)
{
    if(x==nc)
    {
        ans=max(ans,p);
        p^=n[x];
        ans=max(ans,p);
        return;
    }
    dg(p,x+1);
    dg(p^n[x],x+1);
    return;
}
int main()
{
    freopen("xor_equ.in","r",stdin);
	freopen("xor_equ.out","w",stdout);
    cin>>nc;
    for(int i=1;i<=nc;i++) scanf("%lld",&n[i]);
    dg(0,1);
    cout<<ans<<endl;
    return 0;
}