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

int main() {
    int k;
    string s
    cin >> k >> s;
  
  if( s.size() >= k ){
    
    cout << s << endl;
    
  }
  
  else{
    
    cout << s.at(k) << "..." << endl;
    
  }
}
  
