#include <iostream>
#include <cstdio>
#include <algorithm>
#define ll long long 
using namespace std;
inline int read(){
	int x=0,f=1;char c=getchar();
	while(c<'0'||c>'9'){if(c=='-')f=-1;c=getchar();}
	while(c>='0'&&c<='9'){x=(x<<1)+(x<<3)+c-'0';c=getchar();}
	return x*f;
}
const int maxn=10010;
int n;
ll ans;
int data[maxn];
inline void dfs(int cnt,ll num){
	ans=max(ans,num);
	if(cnt==n+1)return ;
	dfs(cnt+1,num^data[cnt]);
	dfs(cnt+1,num);
}
int main(){
	freopen("xor_equ.in","r",stdin);
	freopen("xor_equ.out","w",stdout);
	n=read();
	for(int i=1;i<=n;i++)data[i]=read();
	dfs(1,0);
	cout<<ans<<endl;
	return 0;
}