#include <bits/stdc++.h>
#define int long long
 
using namespace std;
const int N=1e6+5,mod=1e9+7;
void chkmax(int &x,int y){x=max(x,y);}
void chkmin(int &x,int y){x=min(x,y);}
void Add(int &x,int y){x+=y,x%=mod;}
int ab(int x){if(x<0)x=-x;return x;}
int bit(int x,int i){return (x>>i)&1;}

int read(){
	int x=0,f=1;char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
	while(ch>='0'&&ch<='9')x=x*10+(ch-'0'),ch=getchar();
	return x*f;
}

int n,a[N],f[65];
 
int insert(int x,int ok){
  for(int i=60;i>=0;i--){
  	if(!bit(x,i))continue;
  	if(f[i])x^=f[i];
  	else{if(!ok)f[i]=x;return 1;} 
	}	
	return 0;
}

void init(){
	for(int i=1,ok=0;i<=n;i++)ok=insert(a[i],0);
}

signed main(void){
	n=read();
	int sum=0,ans=0;
	for(int i=1;i<=n;i++)a[i]=read(),sum^=a[i];
	init();
	for(int i=1;i<=60;i++){
		int x=(1<<i)-1,ok=insert(x-(1<<(i-1)),1);
		if(!ok)chkmax(ans,sum^x);
	}
	printf("%lld\n",ans);
	return 0;
}
//start coding at
//finish coing at
//accept at