#include <bits/stdc++.h>
using namespace std;
int main() {
  int l, x;
  string s, ch;
  cin >> x;
  cin >> s;
  l = s.length();
  if (x == l) {
    cout << s << "\n";
  } else if (x != l - 1) {
    ch = s.substr(0, x - 1);
    cout << ch << "..."
         << "\n";
  }
  return 0;
}
