#include <bits/stdc++.h>
using namespace std;
int main() {
  int K;
  string S;
  cin >> K;
  cin >> S;
  if (S.size() <= K) {
    cout << S << endl;
  } else {
    for (int i = 0; i < K; i++) {
      cout << S.at(i);
    }
    cout << "..." << endl;
  }
}
