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