#include <bits/stdc++.h>
using namespace std;
int main() {
  int l, x;
  string s, ch;
  cin >> x;
  cin >> s;
  l = s.size();
  if (l == x) {
    cout << s;
  } else {
    for (int i = 0; i < x; i++) {
      ch = s.at(i);
      cout << ch;
    }
    cout << "...";
  }
  return 0;
}
