#include<iostream>
#include<queue>
using namespace std;
int main(){
    int n;
    while(cin>>n){
        priority_queue<int,vector<int>,greater<int>> queue;
        for(int i=0;i<n;i++){
            int x;
            cin>>x;
            queue.push(x);
        }
        int k;
        cin>>k;
        int x;
        for(int i=0;i<k;i++){
            x=queue.top();
            queue.pop();
            while(x==queue.top()){
                queue.pop();
            }
        }
        cout<<x<<endl;
    }
}