#include <bits/stdc++.h>
using namespace std;
int main() {
  int k;
  string s;
  cin >> k >> s;
  if (s.length() <= k) {
    cout << s << endl;
  } else {
    for (int i = k; i < s.length(); i++) {
      s[i] = '.';
    }
    cout << s << endl;
  }
}
