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