/*
TASK:music
LANG:C++
*/
#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
using namespace std;
struct idol
{
       string name;
       float bal;
       int day;
       int h;
};
vector<idol> d;
int n,m,k;
bool cmp(idol A,idol B)
{
     if(A.bal==B.bal)
     {
                     if(A.day==B.day)
                                     return A.h>B.h;
                     else return A.day>B.day;
     }
     else return A.bal<B.bal;
}

inline void work(int K)
{
     sort(d.begin(),d.end(),cmp);
   //  for(int i=0;i<d.size();i++) cout<<d[i].name<<endl;
  //   cout<<"---"<<endl;
     for(int i=1;i<=K;i++) d.pop_back();    
}      
int main()
{
//    freopen("in.tmp","r",stdin);
 //   freopen("out.tmp","w",stdout);
    cin>>n;
    for(int i=1;i<=n;i++)
    {
            cin>>m;
            for(int j=1;j<=m;j++)
            {
                    idol tmp;
                    cin>>tmp.name>>tmp.bal;
                    tmp.day=i;
                    tmp.h=j;
                    d.push_back(tmp);
            }
            cin>>k;
            work(k);
    }

    work(0);
    cout<<d.back().name<<endl;
  
}
