#include<bits/stdc++.h>
#define x first
#define y second
#define PB push_back
#define mst(x,a) memset(x,a,sizeof(x))
#define all(a) begin(a),end(a)
#define rep(x,l,u) for(ll x=l;x<u;x++)
#define rrep(x,l,u) for(ll x=l;x>=u;x--)
#define sz(x) x.size()
#define IOS ios::sync_with_stdio(false);cin.tie(0);
using namespace std;
typedef unsigned long long ull;
typedef pair<int,int> PII;
typedef pair<long,long> PLL;
typedef pair<char,char> PCC;
typedef long long ll;
const int N=205;
const int M=1e6+10;
const int INF=0x3f3f3f3f;
const int MOD=1e9+7;
int a[N],b[N],n,m;
bool check(int x){
rep(i,1,n+1){
bool flag=false;
rep(j,1,m+1){
int res=a[i]&b[j];
if((res|x)==x){
flag=true;
break;
}
}
if(!flag) return false;
}
return true;
}
void solve(){
cin>>n>>m;
rep(i,1,n+1) cin>>a[i];
rep(i,1,m+1) cin>>b[i];
rep(i,0,513){
if(check(i)){
cout<<i<<endl;
break;
}
}
}
int main(){
//IOS;
//freopen("test.txt", "r", stdin);
//freopen("test.txt", "w", stdout);
//int t;cin>>t;
//while(t--)
solve();
return 0;
}