#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 << "\n";
  } else {
    ch = s.substr(0, l - 1);
    cout << ch << "..."
         << "\n";
  }
  return 0;
}
