#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<queue>
using namespace std;
typedef long long LL;
const int SIZEN=2010;
int N;
int id[SIZEN]={0};
LL ans=0;
bool used[SIZEN]={0};
LL f[SIZEN]={0};
void Prim(int s){
	for(int i=1;i<=N;i++) f[i]=-1;
	f[s]=0;int sum=0;
	while(sum<N){
		int mx=-1;
		for(int i=1;i<=N;i++){
			if(used[i]) continue;
			if(mx==-1||f[i]>f[mx]) mx=i;
		}
		if(mx==-1) break;
		sum++;
		used[mx]=1;
		ans+=f[mx];
		for(int i=1;i<=N;i++){
			if(used[i]) continue;
			if(id[i]^id[mx]>f[i]) f[i]=id[i]^id[mx];
		}
	}
}
int main(){
	freopen("superbull.in","r",stdin);
	freopen("superbull.out","w",stdout);
	scanf("%d",&N);
	for(int i=1;i<=N;i++) scanf("%d",&id[i]);
	Prim(1);
	printf("%d\n",ans);
	return 0;
}