#include <bits/stdc++.h>
using namespace std;
int main() {
  unsigned int num;
  cin >> num;
  string str;
  cin >> str;
  if (num >= str.size()) {
    cout << str << endl;
  } else {
    string substr = str.substr(0, num);
    cout << substr << flush;
    cout << "..." << endl;
  }
}
