import java.util.*;
class Main{
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int k = sc.nextInt();
    String s = sc.next();
    int count = s.length();
    String add = "...";
    
    if(count <= k){
      System.out.println(s);
    }else if(count > k){
      String result = s.substring(0, k) + add;
      System.out.println(result);
    }
  }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz