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