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