#include <bits/stdc++.h>
#include <ctime>
//#define endl '\n'
#define ll long long //unsigned long long
#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define PI acos(-1)
#define rep(i,n,m) for(int i=n;i<=m;i++)
#define per(i,n,m) for(int i=n;i>=m;i--)
#define bug1(i) cerr<<i<<endl
#define bug2(i,j) cerr<<i<<" "<<j<<endl
#define bug3(i,j,k) cerr<<i<<" "<<j<<" "<<k<<endl
#define bug4(i,j,k,l) cerr<<i<<" "<<j<<" "<<k<<" "<<l<<endl
#define mod 1000000007 //998244353.1000000007
#define maxn 1000005
#define eps 1e-6
using namespace std;

ll b[65];
bool flag;

void insert(ll x) // 插入数字，获取线性基
{
	for(int i=0;i<=60;i++) if(x>>i&1){
		if(!b[i]){
			b[i]=x;
			return;
		}
		else x^=b[i];
	}
	flag=true;
}

void solve(){
	int n;
	cin>>n;
	ll ans=0;
	rep(i,1,n){
		ll x;cin>>x;
		// cout<<x<<endl;
		ans^=x;
		insert(x);
	}

	for(int i=0;i<=60;i++){
		if(!b[i]){
			ans^=((1LL<<i)-1);
			ans^=(1LL<<i);
			break;
		}
	}
	cout<<ans<<endl;
}

/*

*/
void init(){
	
}
signed main(){
#ifdef LOCAL
	freopen("in.in","r",stdin);
	freopen("out.out","w",stdout);
#endif
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);int ca=1;clock_t c1=clock();
	init();
	// cin>>ca;
	while(ca--){
		solve();
	}
	// cerr<<"Time used:"<<clock()-c1<<"ms"<<endl;
	return 0;
}