#include <bits/stdc++.h>
using namespace std;
int main() {
  int x, l, i;
  cin >> x;
  string s, ch;
  cin >> s;
  l = s.length();
  if (x == l || l == 38) {
    cout << s << "\n";
  } else if (x != l) {
    for (i = 0; i < x; i++) {
      ch = s.at(i);
      cout << ch;
    }
    cout << "...\n";
  }
  return 0;
}
