#include <bits/stdc++.h>
using namespace std;

int main() {
  ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  int n,x; cin>>n;
  map<int,int> ct;
  for (int i=0; i<10*n*5; i++)
    cin>>x, ct[x]++;
  vector<int> ret;
  for (auto &[k,v] : ct)
    if(v>2*n) ret.push_back(k);
  if(ret.empty()) { cout<<-1<<"\n"; return 0; }
  for (auto &e : ret)
    cout<<e<<" ";
  cout<<"\n";
  return 0;
}