#include<iosttream>
#include<vector>
using namespace std;

int main(){
    int n1,n2;
    cin >>n1;
    vector<int> a(n1);
    for(int i=0;i<n1;i++)
        cin >>a[i]
        
    cin >>n2;
    vector<int> b(n2)
    for(int i=0;i<n2;i++)
        cin >> b[i];
        bool found = false;
        int intersction=-1;
        
        for(int i=0;i<n1;i++){
            for(int j=0;j<n2;j++){
                if(a[i]==b[j]){
                    intersection = a[i];
                    found=true;
                    break;
                }
            }if(found)
            break;
        }
        if(found)
           cout<<intersection;
        else
           count<<"the two lists do not intersect";
        return 0;
}