#include <iostream>
#include <list>
using namespace std;
 
 
 
int main()
{    int a,b;
while(cin>>a)
{ list <int> lista;
    while(cin>>b)
    { 
      for(list<int>::iterator i=lista.begin();i!=lista.end();i++)
            if(*i==b)i=lista.erase(i); lista.push_front(b);if(cin.peek() == '\n'||cin.peek()==EOF)break;
    }	
 lista.sort();
    lista.reverse();
    if(lista.size()<a) cout<<'-'<<endl;
    else{
    list<int>::iterator i=lista.begin();
    for(int k=1;k<a;k++)
    i++;
 
    cout<<*i<<endl;} lista.clear();
}
 
    return 0;
}

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5
2 18 18
7 40 30 40 30 29 40 56 47 23 45 20
1 1
2 2 2 2 2 2 2
1 0 0
2 3 0 3