#include <bits/stdc++.h>
using namespace std;
 
int main() {
string s;
int k;
cin >> k;
cin >> s;
int nagasa;
  nagasa = s.size();
  
  if(nagasa <= k)
  {
    cout << s << endl;
  }
  else
  {
    for(int i=0; i<k; i++)
    {
      cout << s[i];
    }
    cout << "..." << endl;
  }

  
  
}