import java.util.*;
public class Main
{
  public static void main(String[] args)
  {
    Scanner sc = new Scanner(System.in);
    int A = sc.nextInt();
    String str = sc.next();
    if(str.length() <= A)
    {
      System.out.println(str);
    }
     else
     {
       String s = str.substring(0,A);
       s = s+"...";
       System.out.println(s);
     }
  }
}

/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